Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation of Revenue [Line Items]
Other revenues	$ 169,382	$ 102,200	$ 391,731	$ 320,132
Total revenues	3,121,332	2,948,694	8,994,400	8,693,006
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(26,521)	(22,957)	(71,705)	(64,516)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	1,515,860	1,535,680	4,538,264	4,529,300
Other revenues	137,149	78,345	317,624	255,204
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	207,327	193,853	629,118	570,380
Other revenues	331	412	1,296	1,181
Other Government Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	219,529	202,936	641,649	603,364
Commercial Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	1,033,523	936,982	2,860,336	2,734,356
Other revenues	16,063	6,484	20,888	16,029
Other
Disaggregation of Revenue [Line Items]
Other revenues	18,071	16,959	56,930	47,708
U.S. dialysis
Disaggregation of Revenue [Line Items]
Total revenues	2,761,017	2,680,296	8,061,383	7,877,073
U.S. dialysis | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(24,289)	(22,957)	(66,698)	(64,516)
U.S. dialysis | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	1,515,860	1,535,680	4,538,264	4,529,300
U.S. dialysis | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	207,327	193,853	629,118	570,380
U.S. dialysis | Other Government Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	90,549	86,852	265,119	253,731
U.S. dialysis | Commercial Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	965,331	880,812	2,676,758	2,570,054
U.S. dialysis | Other
Disaggregation of Revenue [Line Items]
Other revenues	6,239	6,056	18,822	18,124
Other—Ancillary services
Disaggregation of Revenue [Line Items]
Total revenues	360,315	268,398	933,017	815,933
Other—Ancillary services | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(2,232)		(5,007)
Other—Ancillary services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Other revenues	137,149	78,345	317,624	255,204
Other—Ancillary services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Other revenues	331	412	1,296	1,181
Other—Ancillary services | Other Government Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	128,980	116,084	376,530	349,633
Other—Ancillary services | Commercial Payors
Disaggregation of Revenue [Line Items]
Dialysis patient service revenues	68,192	56,170	183,578	164,302
Other revenues	16,063	6,484	20,888	16,029
Other—Ancillary services | Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 11,832	$ 10,903	$ 38,108	$ 29,584