Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Other revenues	$ 100,379	$ 142,416	$ 304,346	$ 392,154
Total revenues	2,938,319	2,924,066	8,674,830	8,645,282
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(22,104)	(41,396)	(74,718)	(117,389)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,543,819	1,541,707	4,586,278	4,619,852
Other revenues	77,277	111,248	243,085	309,555
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	203,169	193,254	585,053	547,045
Other revenues	377	412	981	1,061
Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	195,884	181,646	583,678	537,085
Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	917,075	902,092	2,685,671	2,653,257
Other revenues	7,164	7,799	14,387	27,370
Other
Disaggregation of Revenue [Line Items]
Other revenues	15,658	27,304	50,415	67,446
U.S. dialysis
Disaggregation of Revenue [Line Items]
Total revenues	2,675,942	2,656,902	7,893,839	7,880,798
U.S. dialysis \| Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(22,104)	(37,317)	(70,424)	(104,987)
U.S. dialysis \| Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,543,819	1,541,707	4,586,278	4,619,852
U.S. dialysis \| Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	203,169	193,254	585,053	547,045
U.S. dialysis \| Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	82,624	83,602	245,125	253,654
U.S. dialysis \| Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	862,218	858,247	2,528,499	2,534,388
U.S. dialysis \| Other
Disaggregation of Revenue [Line Items]
Other revenues	6,216	17,409	19,308	30,846
Other—Ancillary services
Disaggregation of Revenue [Line Items]
Total revenues	262,377	267,164	780,991	764,484
Other—Ancillary services \| Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	(4,079)	(4,294)	(12,402)
Other—Ancillary services \| Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Other revenues	77,277	111,248	243,085	309,555
Other—Ancillary services \| Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Other revenues	377	412	981	1,061
Other—Ancillary services \| Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	113,260	98,044	338,553	283,431
Other—Ancillary services \| Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	54,857	43,845	157,172	118,869
Other revenues	7,164	7,799	14,387	27,370
Other—Ancillary services \| Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 9,442	$ 9,895	$ 31,107	$ 36,600