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Summary of Significant Accounting Policies - Stock-Based Compensation (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock-based compensation expense | $ 4,713 | $ 5,846 | $ 11,353
Income tax benefits | 990 | 1,228 | 2,384
Excess tax benefits (expenses) on settled share-based employee payments | $ 909 | $ (165) | $ 612
Restricted Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted during the year | 62,594 | 45,540 | 50,061
Shares vested during the year | 34,854 | 56,203 | 48,228
Unvested shares at end of year | 96,127 | 71,706 | 93,351
Unrecognized compensation expense at end of year (in thousands) | $ 2,215 | $ 2,003 | $ 2,054
Total Shareholder Return Market-Based Awards [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted during the year | 64,910 | 47,848 | 99,214
Shares vested during the year | 77,174 | 71,299 | 106,858
Shares earned based on market metrics | 58,652 |  |
Unvested shares at end of year | 107,854 | 122,133 | 178,035
Unrecognized compensation expense at end of year (in thousands) | $ 2,653 | $ 2,296 | $ 3,377
Performance Shares [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares granted during the year | 64,910 | 47,848 | 49,609
Shares vested during the year | 38,590 | 35,622 | 53,454
Shares earned based on market metrics | 26,627 | 63,763 | 106,908
Unvested shares at end of year | 107,854 | 83,464 | 88,990
Unrecognized compensation expense at end of year (in thousands) | $ 1,223 | $ 1,090 | $ 2,401

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