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Employee Stock Purchase and Equity-Based Compensation Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Stock-based compensation expense, net of tax benefits | $ 7.3 | $ 49.0 | $ 16.3
Stock-based compensation expense, tax benefits | 2.5 | 16.7 | 0.2
Stock-based compensation expense, tax benefit realized related to awards vested | 11.2 | $ 3.3 | $ 0.2
Compensation cost related to non-vested awards not yet recognized | $ 16.5 |  |
Vesting period | 6 years |  |
Common stock related to employee statutory income tax withholding, shares retired | 36,921 | 27,962 |
Stock Appreciation Rights |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Number of years over which share price increase | 3 years |  |
Vesting period | 3 years |  |
Long-Term Growth Units |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period | 3 years |  |
Restricted Stock Units |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Vesting period | 3 years |  |
Share issued | 78,476 | 74,704 |
Employee Stock Purchase Plan |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |
Percentage of per-share market value limit for share purchases | 5.00% |  |
Average purchase price | $ 34.53 |  |

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