Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Other revenues	$ 127,956	$ 113,423
Total revenues	2,841,237	2,743,112
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(36,394)	(33,977)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,502,222	1,493,516
Other revenues	98,478	61,700
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	171,467	154,190
Other revenues	366	6
Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	206,484	190,602
Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	865,049	821,801
Other revenues	10,521	32,619
Other
Disaggregation of Revenue [Line Items]
Other revenues	23,044	22,655
U.S. dialysis and related lab services
Disaggregation of Revenue [Line Items]
Total revenues	2,584,381	2,516,510
U.S. dialysis and related lab services | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(32,242)	(30,641)
U.S. dialysis and related lab services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,502,222	1,493,516
U.S. dialysis and related lab services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	171,467	154,190
U.S. dialysis and related lab services | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	111,910	106,127
U.S. dialysis and related lab services | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	825,582	788,413
U.S. dialysis and related lab services | Other
Disaggregation of Revenue [Line Items]
Other revenues	5,442	4,905
Other—Ancillary services
Disaggregation of Revenue [Line Items]
Total revenues	256,856	226,602
Other—Ancillary services | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(4,152)	(3,336)
Other—Ancillary services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Other revenues	98,478	61,700
Other—Ancillary services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Other revenues	366	6
Other—Ancillary services | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	94,574	84,475
Other—Ancillary services | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	39,467	33,388
Other revenues	10,521	32,619
Other—Ancillary services | Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 17,602	$ 17,750