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Treasury Stock - Additional Information (Details) - USD ($) | 6 Months Ended |
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Jun. 30, 2021 | Oct. 17, 2016
Equity, Class of Treasury Stock [Line Items] |  |
Treasury stock (in shares) | 64,704,383 |
2016 BOD Authorized Common Stock Repurchase |  |
Equity, Class of Treasury Stock [Line Items] |  |
Stock repurchase program, additional repurchase authorization |  | $ 300,000,000.0
Remaining authorized repurchase amount | $ 76,600,000 |
2004 Amended and Restated Stock Incentive Plan |  |
Equity, Class of Treasury Stock [Line Items] |  |
Treasury shares issued for restricted stock units that vested during the period (in shares) | 573,232 |
Average cost of treasury shares that were issued for restricted stock units that vested during the period (usd per share) | $ 3.19 |
Shares repurchased to satisfy minimum employee withholding tax requirements resulting from the vesting of such restricted stock units (in shares) | 222,146 |
Average cost per share of treasury stock acquired (usd per share) | $ 38.44 |

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