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Employee Benefits - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items] |  |  |
Employer matching contribution, percent | 4.00% |  |
Maximum annual contribution per employee, amount | $ 7,200 |  |
Defined contribution plan cost recognized | 43,900,000 | $ 44,100,000 | $ 36,700,000
Compensation expense related to deferred compensation plan | 1,900,000 | 600,000 | $ 1,700,000
Other assets | 10,000,000.0 | 8,900,000 |
Other assets |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Deferred compensation plan assets | 88,500,000 | 75,700,000 |
Other liabilities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Deferred compensation liability | $ 94,500,000 | $ 79,600,000 |

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