| **Share-Based Compensation - Components of Share-Based Compensation Awards (Details) - USD ($) $ in Thousands** | 3 Months Ended | 9 Months Ended | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------|----------------|----------------|-----------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                              |           |           |            |   |   |
| Pre-tax compensation expense                                                                                    | $ 648          | $ 556          | $ 1,883         | $ 1,687 | $ 1,687 |
| Income tax expense (benefit)                                                                                    | (218)          | (182)          | (628)           | (548) |   |
| Total share-based compensation expense, net of income taxes                                                     | 430            | 374            | 1,255           | 1,139 |   |
| Stock and ESPP Options                                                                                          |           |           |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                              |           |           |            |   |   |
| Pre-tax compensation expense                                                                                    | 18             | 23             | 54              | 78 |   |
| Income tax expense (benefit)                                                                                    | 3              | 5              | 12              | 4 |   |
| Total share-based compensation expense, net of income taxes                                                     | 21             | 28             | 66              | 82 |   |
| Restricted Stock Awards                                                                                         |           |           |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**                              |           |           |            |   |   |
| Pre-tax compensation expense                                                                                    | 630            | 533            | 1,829           | 1,609 |   |
| Income tax expense (benefit)                                                                                    | (221)          | (187)          | (640)           | (552) |   |
| Total share-based compensation expense, net of income taxes                                                     | $ 409          | $ 346          | $ 1,189         | $ 1,057 |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                       |
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| X                                                                                                                                                                                    |
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