Amortizable Intangible Assets - Amortizable Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 2,349,192	$ 2,200,061
Accumulated amortization	(1,267,727)	(1,150,401)
Net carrying value	1,081,465	1,049,660
Purchased Customer Accounts
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	2,311,605	2,164,968
Accumulated amortization	(1,235,261)	(1,118,316)
Net carrying value	$ 1,076,344	$ 1,046,652
Weighted average life (years)	14 years 10 months 24 days	15 years
Non-compete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 37,587	$ 35,093
Accumulated amortization	(32,466)	(32,085)
Net carrying value	$ 5,121	$ 3,008
Weighted average life (years)	4 years 6 months	4 years 7 months 6 days