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Summary Of Significant Accounting Policies Summary of Significant Accounting Policies (Stock-Based Compensation) (Details) - USD ($) $ in Thousands | 12 Months Ended | 24 Months Ended
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-based Payment Arrangement, Expense | $ 11,353 | $ 5,367 | $ 7,359 |
Income tax benefits | 2,384 | 1,127 | 2,576 |
Excess tax benefits on settled share-based employee payments | $ (612) | $ 990 | $ 2,348 |
Federal statutory tax rate | 21.00% | 21.00% | 35.00% | 21.00%
Restricted Stock [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award Vesting Period | 3 years |  |  |
Shares granted during the year | 50,061 | 40,661 | 57,746 |
Shares vested during the year | (48,228) | (53,352) | (57,473) |
Unvested shares at end of year | 93,351 | 91,998 | 106,053 | 93,351
Unrecognized compensation expense at end of year (in thousands) | $ 2,054 | $ 1,964 | $ 1,853 | $ 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 | 99,214 | 80,724 | 114,390 |
Shares vested during the year | (106,858) | (107,342) | (107,649) |
Shares earned based on market metrics | 0 | 0 | 158,262 |
Unvested shares at end of year | 178,035 | 187,172 | 218,507 | 178,035
Unrecognized compensation expense at end of year (in thousands) | $ 3,377 | $ 3,706 | $ 2,849 | $ 3,377
Performance Shares [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Shares granted during the year | 49,609 | 40,329 | 57,223 |
Shares vested during the year | (53,454) | (53,699) | (53,862) |
Shares earned based on market metrics | 106,908 | 30,102 | 41,502 |
Unvested shares at end of year | 88,990 | 93,579 | 108,581 | 88,990
Unrecognized compensation expense at end of year (in thousands) | $ 2,401 | $ 1,260 | $ 1,856 | $ 2,401
Total Shareholder Return Market-Based Awards and Performance Awards [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Award Vesting Period | 3 years |  |  |
Dividend Component Liability, Current | $ 900 | $ 300 |  | $ 900
Minimum [Member] | Total Shareholder Return Market-Based Awards and Performance Awards [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock issued range, percent of the performance shares granted | 0.00% |  |  | 0.00%
Maximum [Member] | Total Shareholder Return Market-Based Awards and Performance Awards [Member] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Common stock issued range, percent of the performance shares granted | 200.00% |  |  | 200.00%

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