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Share-Based Payments, Deferred Compensation and Employee Ownership Plans - Restricted Shares and Other Share Based Payments Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 01, 2022	Dec. 31, 2021
Equity Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Expense	$ 21.6	$ 28.2
Share-based Payment Arrangement, Expense, Tax Benefit	$ 7.0	$ 10.8
Equity Plans \| Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number				972,732
Equity Plans \| Restricted Stock Units (RSUs) \| Non-employee Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, shares	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Other	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	246,333			259,536
2022 Equity Unit Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 1.3
Granted, shares	1,487,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized			2,000,000
Share-based Payment Arrangement, Expense	$ 0.3
Share-based Payment Arrangement, Expense, Tax Benefit	$ 0.1