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Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Accounting Policies [Abstract] |  |  |
Excess tax benefits from stock-based compensation | $ 4.2 | $ 10.9 | $ 10.5
Cumulative Effect Period Of Adoption | $ 1.3 | $ 0.3 | $ 6.2

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- Definition Amount of tax benefit for recognition of expense of award under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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