Amortizable Intangible Assets - Amortizable Intangible Assets (Details) - USD ($) $ in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Gross carrying value		$ 2,469.9	$ 2,349.2
Accumulated amortization		(1,298.9)	(1,267.7)
Net carrying value		1,171.0	1,081.5
Purchased Customer Accounts
Finite-Lived Intangible Assets [Line Items]
Gross carrying value		2,432.0	2,311.6
Accumulated amortization		(1,266.0)	(1,235.3)
Net carrying value		$ 1,166.0	$ 1,076.3
Weighted average life (years)	[1]	14 years 8 months 12 days	14 years 10 months 24 days
Non-compete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross carrying value		$ 37.9	$ 37.6
Accumulated amortization		(32.9)	(32.4)
Net carrying value		$ 5.0	$ 5.2
Weighted average life (years)	[1]	4 years 6 months	4 years 6 months

[1] Weighted average life calculated as of the date of acquisition.