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Stock-Based Compensation - Narrative (Details) | 12 Months Ended
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Dec. 31, 2019 USD ($) plan shares | Dec. 31, 2018 USD ($) shares | Dec. 31, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Number of stock-based compensation plans | plan | 2 |  |
Options expiration period | 10 years |  |
Stock option awards granted | shares | 0 | 0 |
Stock compensation expense | $ 8,000,000.0 | $ 5,600,000 | $ 3,800,000
Intrinsic value of fully-vested stock options outstanding | 5,800,000 |  |
Stock Option |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock compensation expense |  | 0 |
Tax benefits from stock-based compensation |  | 0 |
Total intrinsic value of options exercised | 4,900,000 | 4,900,000 | 6,300,000
Proceeds from Stock Options Exercised | 1,000,000.0 | 1,800,000 | 2,400,000
Common Stock Redeemed For Payment of Stock Option Exercises, Aggregate Value | 2,000,000.0 | 1,600,000 | 2,800,000
Restricted Stock [Member] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock compensation expense |  | 5,600,000 | 3,300,000
Tax benefits from stock-based compensation | $ 400,000 | $ 200,000 | $ 600,000
Stock issued during period, shares, restricted stock award | shares | 230,922 |  |
Unrecognized compensation cost related to nonvested restricted stock awards | $ 8,100,000 |  |
Unrecognized compensation cost related to nonvested restricted stock to be recognized over weighted average period (in years) | 1 year 1 month 6 days |  |
Restricted Stock [Member] | Upon Achievement of Performance Goals |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock issued during period, shares, restricted stock award | shares | 72,926 |  |
Restricted Stock [Member] | Upon Achievement of Defined Return on Equity Performance Goals |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock issued during period, shares, restricted stock award | shares | 36,463 |  |
Restricted Stock [Member] | Upon Achievement of Defined Total Return to Shareholder Goals |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock issued during period, shares, restricted stock award | shares | 36,463 |  |
Restricted Stock [Member] | Upon One-Third Annual Anniversary |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Stock issued during period, shares, restricted stock award | shares | 139,661 |  |
Restricted Stock [Member] | First Anniversary |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Annual vesting percentage |  | 33.33% |
Restricted Stock [Member] | Second Anniversary |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Annual vesting percentage |  | 33.33% |
Restricted Stock [Member] | Third Anniversary |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Annual vesting percentage |  | 33.33% |
2006 Plan |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Shares available for grant | shares | 1,492,762 |  |

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