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Coworker Retirement and Other Compensation Benefits - Coworker Stock Purchase Plan (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Coworker Retirement and Other Compensation Benefits [Line Items] |  |  |
Equity-based compensation expense | $ 48,500,000 | $ 40,700,000 | $ 43,700,000
Coworker Stock Purchase Plan |  |  |
Coworker Retirement and Other Compensation Benefits [Line Items] |  |  |
Employee stock purchase plan discount to market price (as percent) | 5.00% |  |
Equity-based compensation expense | $ 0 |  |

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- Definition [Line Items] for Coworker Retirement and Other Compensation Benefits [Table] + References No definition available. + Details
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- Definition Employee Stock Purchase Plan, discount to market price, percent + References No definition available. + Details
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