Goodwill and Other Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands		12 Months Ended
	Feb. 26, 2021	Dec. 31, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets		$ (1,866,363)	$ (1,526,153)
Gross Carrying Amount		67,300	67,300
Net Carrying Value		67,300	67,300
Gross Carrying Amount		5,151,400	5,110,340
Net Carrying Value		$ 3,285,037	3,584,187
Client relationships
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period	16 years	15 years
Gross Carrying Amount		$ 4,178,280	4,138,460
Amortization of intangible assets		(1,531,679)	(1,252,892)
Net Carrying Value		$ 2,646,601	2,885,568
Provider Network
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period		15 years
Gross Carrying Amount		$ 896,800	896,800
Amortization of intangible assets		(332,812)	(273,026)
Net Carrying Value		$ 563,988	623,774
Technology
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period		5 years
Gross Carrying Amount		$ 6,350	6,350
Amortization of intangible assets		(1,482)	(211)
Net Carrying Value		$ 4,868	6,139
Trade Names
Finite-Lived Intangible Assets [Line Items]
Weighted-average amortization period	10 years	9 years
Gross Carrying Amount		$ 2,670	1,430
Amortization of intangible assets		(390)	(24)
Net Carrying Value		$ 2,280	$ 1,406