Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Other revenues	$ 98,553	$ 121,782	$ 203,967	$ 249,738
Total revenues	2,916,510	2,879,979	5,736,511	5,721,216
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(21,317)	(39,600)	(52,614)	(75,994)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,562,164	1,547,113	3,042,461	3,078,146
Other revenues	80,211	99,829	165,807	198,307
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	194,641	182,324	381,884	353,791
Other revenues	305	283	605	649
Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	200,781	177,767	387,794	355,439
Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	881,618	886,115	1,768,595	1,751,164
Other revenues	1,189	9,050	7,223	19,571
Other
Disaggregation of Revenue [Line Items]
Other revenues	16,918	17,098	34,756	40,143
U.S. dialysis
Disaggregation of Revenue [Line Items]
Total revenues	2,655,021	2,639,515	5,217,897	5,223,897
U.S. dialysis | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(21,317)	(35,429)	(48,320)	(67,670)
U.S. dialysis | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,562,164	1,547,113	3,042,461	3,078,146
U.S. dialysis | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	194,641	182,324	381,884	353,791
U.S. dialysis | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	82,317	86,954	162,501	170,052
U.S. dialysis | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	830,801	850,558	1,666,280	1,676,140
U.S. dialysis | Other
Disaggregation of Revenue [Line Items]
Other revenues	6,415	7,995	13,091	13,438
Other—Ancillary services
Disaggregation of Revenue [Line Items]
Total revenues	261,489	240,464	518,614	497,319
Other—Ancillary services | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	0	(4,171)	(4,294)	(8,324)
Other—Ancillary services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Other revenues	80,211	99,829	165,807	198,307
Other—Ancillary services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Other revenues	305	283	605	649
Other—Ancillary services | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	118,464	90,813	225,293	185,387
Other—Ancillary services | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	50,817	35,557	102,315	75,024
Other revenues	1,189	9,050	7,223	19,571
Other—Ancillary services | Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 10,503	$ 9,103	$ 21,665	$ 26,705