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Stock-based Compensation and Other Employee Benefit Plans Employee Benefit Plans (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Defined Benefit Plans and Other Postretirement Benefit Plans [Abstract] |  |  |
Deferred Compensation Plan Assets | $ 11.8 | $ 6.2 |
Defined Contribution Plan, Employer Discretionary Contribution Amount | $ 16.2 | $ 13.0 | $ 7.5

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- Definition Defined Benefit Plans and Other Postretirement Benefit Plans [Abstract] + References No definition available. + Details
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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