Share-Based Compensation - Compensation Expense for Share-Based Awards (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact on income before income taxes	$ 15.3	$ 12.3
Income tax benefit	(3.8)	(3.1)
Share-based compensation expense, net of tax benefit	11.5	9.2
Restricted Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact on income before income taxes	11.9	9.2
Performance Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Impact on income before income taxes	$ 3.4	$ 3.1

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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