Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Patient service revenues	$ 2,635,152	$ 2,591,074
Other revenues	113,423	232,825
Total revenues	2,743,112	2,849,444
Intersegment Elimination
Disaggregation of Revenue [Line Items]
Total revenues	(33,977)	(28,621)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,493,516	1,485,192
Other revenues	61,700	142,758
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	154,190	157,496
Other revenues	6	15,791
Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	190,602	189,656
Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	821,801	802,697
Other revenues	32,619	40,420
Other
Disaggregation of Revenue [Line Items]
Other revenues	22,655	44,055
U.S. dialysis and related lab services
Disaggregation of Revenue [Line Items]
Total revenues	2,516,510	2,519,478
U.S. dialysis and related lab services | Intersegment Elimination
Disaggregation of Revenue [Line Items]
Total revenues	(30,641)	(18,422)
U.S. dialysis and related lab services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,493,516	1,485,192
Other revenues	0	0
U.S. dialysis and related lab services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	154,190	157,496
Other revenues	0	0
U.S. dialysis and related lab services | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	106,127	107,119
U.S. dialysis and related lab services | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	788,413	782,979
Other revenues	0	0
U.S. dialysis and related lab services | Other
Disaggregation of Revenue [Line Items]
Other revenues	4,905	5,114
Other—Ancillary services and strategic initiatives
Disaggregation of Revenue [Line Items]
Total revenues	226,602	329,966
Other—Ancillary services and strategic initiatives | Intersegment Elimination
Disaggregation of Revenue [Line Items]
Total revenues	(3,336)	(10,199)
Other—Ancillary services and strategic initiatives | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	0	0
Other revenues	61,700	142,758
Other—Ancillary services and strategic initiatives | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	0	0
Other revenues	6	15,791
Other—Ancillary services and strategic initiatives | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	84,475	82,537
Other—Ancillary services and strategic initiatives | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	33,388	19,718
Other revenues	32,619	40,420
Other—Ancillary services and strategic initiatives | Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 17,750	$ 38,941