Goodwill - Changes in Carrying Value of Goodwill by Reportable Segments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 6,919,109	$ 6,787,635
Acquisitions	173,244	130,057
Divestitures	(1,745)	(8,293)
Foreign currency and other adjustments	(44,367)	9,710
Ending balance	7,046,241	6,919,109
Goodwill	7,172,448
Accumulated impairment charges	(126,207)
U.S. dialysis
Goodwill [Roll Forward]
Beginning balance	6,309,928	6,287,100
Acquisitions	91,979	24,377
Divestitures	(1,745)	(1,549)
Foreign currency and other adjustments	0	0
Ending balance	6,400,162	6,309,928
Goodwill	6,400,162
Accumulated impairment charges	0
Other - Ancillary services
Goodwill [Roll Forward]
Beginning balance	609,181	500,535
Acquisitions	81,265	105,680
Divestitures	0	(6,744)
Foreign currency and other adjustments	(44,367)	9,710
Ending balance	646,079	$ 609,181
Goodwill	772,286
Accumulated impairment charges	$ (126,207)