| **Pay vs Performance Disclosure - USD ($)**                          | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            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| **Pay vs Performance Disclosure [Table]**                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |   |   |
| Pay vs Performance [Table Text Block]                                | ​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

​

**(a)**

​

**(b)**

​

**(b-2)**

​

**(c)**

​

**(c-2)**

​

**(d)**

​

**(e)**

​

**(f)**

​

**(g)**

​

**(h)**

​

** **

​

** **

​

** **

​

** **

​

** **

**Average**

** **

​

** **

**Value of Initial Fixed $100**

** **

​

​

** **

​

** **

​

** **

​

** **

​

** **

**Summary**

** **

**Average**

** **

**Investment Based on:**

** **

​

​

** **

**Summary**

** **

**Summary**

** **

**Compensation**

** **

**Compensation**

** **

**Compensation**

** **

**Compensation**

** **

​

** **

**Peer**

** **

​

​

** **

**Compensation**

** **

**Compensation**

** **

**Actually**

** **

**Actually**

** **

**Table**

** **

**Actually**

** **

**NL**

** **

**Group**

** **

**Net**

​

** **

**Table**

** **

**Table**

** **

**Paid to**

** **

**Paid to**

** **

**Total for**

** **

**Paid to**

** **

**Total**

** **

**Total**

** **

**Income**

​

** **

**Total for PEO**

** **

**Total for PEO**

** **

**PEO**

** **

**PEO**

** **

**Non-PEO**

** **

**Non-PEO**

** **

**Shareholder**

** **

**Shareholder**

** **

**(Loss)**

​

** **

**Graham (1)**

** **

**Riley (1)**

** **

**Graham (1)(2)**

** **

**Riley (1)(2)**

** **

**NEOs (3)**

** **

**NEOs (2)(3)**

** **

**Return (4)**

** **

**Return (4)**

** **

**($) (in**

**Year**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**($)**

** **

**thousands)**

2022

​

n/a

​

 1,077,000

​

n/a

​

 1,077,000

​

 1,930,400

​

 1,930,400

​

 56

​

 97

​

 36,456

2021

​

 6,138,000

​

 945,000

​

 6,138,000

​

 945,000

​

 788,250

​

 788,250

​

 56

​

 106

​

 53,360

2020

​

 6,675,000

​

n/a

​

 6,675,000

​

n/a

​

 1,256,400

​

 1,256,400

​

 35

​

 101

​

 16,103

2019

​

 5,660,000

​

n/a

​

 5,660,000

​

n/a

​

 1,668,200

​

 1,668,200

​

 27

​

 91

​

 28,035

2018

​

 4,887,000

​

n/a

​

 4,887,000

​

n/a

​

 2,014,250

​

 2,014,250

​

 25

​

 73

​

 (39,013)

(1)

Our only PEO for 2018 through 2020 was Robert D. Graham, and our only PEO for 2022 was Courtney J. Riley.  In 2021, we had two PEOs: Mr. Graham served as our chief executive officer until June 2021, when Courtney J. Riley succeeded him in that position.  Both Ms. Riley and Mr. Graham were executive officers for all of 2021, with Ms. Riley previously serving as president until her promotion in June 2021 and with Mr. Graham continuing to serve as our vice chairman; the 2021 amounts for each of them in this table reflect the full year.

(2)

For purposes of this table, the term “compensation actually paid” is the total compensation reported in the Summary Compensation Table in our proxy statement, adjusted (if applicable) as required by SEC rules; no such adjustments are applicable for the officers and years reported in this table. See the footnotes to our Summary Compensation Table in the applicable year’s proxy statement for a discussion of what we report for compensation for our named executive officers who are Contran employees and perform services to us and our subsidiaries pursuant to the ISA.  

​

(3)

The non-PEO NEOs for each year were as follows:

2022:  Michael S. Simmons, Andrew B. Nace, Amy A. Samford, John R. Powers, III, Robert D. Graham  

2021:  Andrew B. Nace, Amy A. Samford, Patricia A. Kropp, John R. Powers, III   

2020:  Courtney J. Riley, Andrew B. Nace, Amy A. Samford, Clarence B. Brown, III, Kelly D. Luttmer

2019:  Courtney J. Riley, Kelly D. Luttmer, Andrew B. Nace, Amy A. Samford, Gregory M. Swalwell

2018:  Courtney J. Riley, Gregory M. Swalwell, Kelly D. Luttmer, Andrew B. Nace   

​

(4)

Total shareholder return (TSR) amounts show the value at December 31 of each year, assuming an original investment of $100 at December 31, 2017 and reinvestment of cash dividends and other distributions to stockholders. For the peer group TSR, the peer group is the same as in our performance graph in Part II, Item 5 of our annual report on Form 10-K for the fiscal year ended December 31, 2022:  the S&P 500 Industrial Conglomerates Index. |   |   |   |   |
| Named Executive Officers, Footnote [Text Block]                      | (1)

Our only PEO for 2018 through 2020 was Robert D. Graham, and our only PEO for 2022 was Courtney J. Riley.  In 2021, we had two PEOs: Mr. Graham served as our chief executive officer until June 2021, when Courtney J. Riley succeeded him in that position.  Both Ms. Riley and Mr. Graham were executive officers for all of 2021, with Ms. Riley previously serving as president until her promotion in June 2021 and with Mr. Graham continuing to serve as our vice chairman; the 2021 amounts for each of them in this table reflect the full year.

(3)

The non-PEO NEOs for each year were as follows:

2022:  Michael S. Simmons, Andrew B. Nace, Amy A. Samford, John R. Powers, III, Robert D. Graham  

2021:  Andrew B. Nace, Amy A. Samford, Patricia A. Kropp, John R. Powers, III   

2020:  Courtney J. Riley, Andrew B. Nace, Amy A. Samford, Clarence B. Brown, III, Kelly D. Luttmer

2019:  Courtney J. Riley, Kelly D. Luttmer, Andrew B. Nace, Amy A. Samford, Gregory M. Swalwell

2018:  Courtney J. Riley, Gregory M. Swalwell, Kelly D. Luttmer, Andrew B. Nace   

​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |   |   |   |   |
| Peer Group Issuers, Footnote [Text Block]                            | (4)

Total shareholder return (TSR) amounts show the value at December 31 of each year, assuming an original investment of $100 at December 31, 2017 and reinvestment of cash dividends and other distributions to stockholders. For the peer group TSR, the peer group is the same as in our performance graph in Part II, Item 5 of our annual report on Form 10-K for the fiscal year ended December 31, 2022:  the S&P 500 Industrial Conglomerates Index.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |   |   |   |   |
| Adjustment To PEO Compensation, Footnote [Text Block]                | (2)

For purposes of this table, the term “compensation actually paid” is the total compensation reported in the Summary Compensation Table in our proxy statement, adjusted (if applicable) as required by SEC rules; no such adjustments are applicable for the officers and years reported in this table. See the footnotes to our Summary Compensation Table in the applicable year’s proxy statement for a discussion of what we report for compensation for our named executive officers who are Contran employees and perform services to us and our subsidiaries pursuant to the ISA.  

​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |   |   |   |   |
| Non-PEO NEO Average Total Compensation Amount                        | $ 1,930,400                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | $ 788,250 | $ 1,256,400 | $ 1,668,200 | $ 2,014,250 |
| Non-PEO NEO Average Compensation Actually Paid Amount                | $ 1,930,400                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | 788,250 | 1,256,400 | 1,668,200 | 2,014,250 |
| Adjustment to Non-PEO NEO Compensation Footnote [Text Block]         | (2)

For purposes of this table, the term “compensation actually paid” is the total compensation reported in the Summary Compensation Table in our proxy statement, adjusted (if applicable) as required by SEC rules; no such adjustments are applicable for the officers and years reported in this table. See the footnotes to our Summary Compensation Table in the applicable year’s proxy statement for a discussion of what we report for compensation for our named executive officers who are Contran employees and perform services to us and our subsidiaries pursuant to the ISA.  

​                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |   |   |   |   |
| Compensation Actually Paid vs. Total Shareholder Return [Text Block] | The following chart shows the relationship between the amounts in columns (c) and (c-2) and in column (e) of the Pay Versus Performance Table, and the total shareholder return (TSR) amounts in columns (f) and (g) of the Pay Versus Performance Table.  It also shows the relationship between our TSR and the peer group TSR.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |   |   |   |   |
| Compensation Actually Paid vs. Net Income [Text Block]               | The following chart shows the relationship between the amounts in columns (c) and (c-2) and in column (e) of the Pay Versus Performance Table, and our net income as shown in column (h) of the Pay Versus Performance Table.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |   |   |   |   |
| Total Shareholder Return Vs Peer Group [Text Block]                  | The following chart shows the relationship between the amounts in columns (c) and (c-2) and in column (e) of the Pay Versus Performance Table, and the total shareholder return (TSR) amounts in columns (f) and (g) of the Pay Versus Performance Table.  It also shows the relationship between our TSR and the peer group TSR.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |   |   |   |   |
| Total Shareholder Return Amount                                      | $ 56                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 56 | 35 | 27 | 25 |
| Peer Group Total Shareholder Return Amount                           | 97                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               | 106 | 101 | 91 | 73 |
| Net Income (Loss)                                                    | $ 36,456,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     | 53,360,000 | 16,103,000 | 28,035,000 | (39,013,000) |
| PEO Name                                                             | J. Riley                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |   |   |   |   |
| Graham                                                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |   |   |
| **Pay vs Performance Disclosure [Table]**                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |   |   |
| PEO Total Compensation Amount                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 6,138,000 | 6,675,000 | 5,660,000 | 4,887,000 |
| PEO Actually Paid Compensation Amount                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             | 6,138,000 | $ 6,675,000 | $ 5,660,000 | $ 4,887,000 |
| Riley                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |   |   |
| **Pay vs Performance Disclosure [Table]**                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |   |   |   |   |
| PEO Total Compensation Amount                                        | $ 1,077,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | 945,000 |   |   |   |
| PEO Actually Paid Compensation Amount                                | $ 1,077,000                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | $ 945,000 |   |   |   |

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.
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