| **Share-Based Compensation - Components of Awards (Details) - USD ($) $ in Thousands** | 12 Months Ended |
|----------------------------------------------------------------------------------------|-----------------|
||
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**     |            |   |   |
| Pre-tax compensation expense                                                           | $ 2,270         | $ 2,177 | $ 1,773 |
| Income tax expense (benefit)                                                           | (745)           | (726) | (547) |
| Total share-based compensation expense, net of income taxes                            | 1,525           | 1,451 | 1,226 |
| Stock and ESPP Options                                                                 |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**     |            |   |   |
| Pre-tax compensation expense                                                           | 101             | 237 | 253 |
| Income tax expense (benefit)                                                           | 4               | (47) | (16) |
| Total share-based compensation expense, net of income taxes                            | 105             | 190 | 237 |
| Restricted Stock Awards                                                                |            |   |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]**     |            |   |   |
| Pre-tax compensation expense                                                           | 2,169           | 1,940 | 1,520 |
| Income tax expense (benefit)                                                           | (749)           | (679) | (531) |
| Total share-based compensation expense, net of income taxes                            | $ 1,420         | $ 1,261 | $ 989 |

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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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=d3e5070-113901Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 14 -Section F
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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
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| - 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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