Revenue Recognition Segment Revenue by Payor (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Disaggregation of Revenue [Line Items]
Other revenues	$ 112,665	$ 101,274
Total revenues	2,872,699	2,817,555
Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(23,415)	(22,169)
Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,482,767	1,464,086
Other revenues	93,238	83,596
Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	205,776	189,655
Other revenues	570	538
Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	203,629	197,695
Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	889,909	887,004
Other revenues	1,206	1,338
Other
Disaggregation of Revenue [Line Items]
Other revenues	19,019	15,812
U.S. dialysis
Disaggregation of Revenue [Line Items]
Total revenues	2,590,113	2,552,927
U.S. dialysis | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(22,047)	(22,169)
U.S. dialysis | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Patient service revenues	1,482,767	1,464,086
U.S. dialysis | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Patient service revenues	205,776	189,655
U.S. dialysis | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	82,044	80,800
U.S. dialysis | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	835,393	834,579
U.S. dialysis | Other
Disaggregation of Revenue [Line Items]
Other revenues	6,180	5,976
Other—Ancillary services
Disaggregation of Revenue [Line Items]
Total revenues	282,586	264,628
Other—Ancillary services | Elimination of intersegment revenues
Disaggregation of Revenue [Line Items]
Total revenues	(1,368)
Other—Ancillary services | Medicare and Medicare Advantage
Disaggregation of Revenue [Line Items]
Other revenues	93,238	83,596
Other—Ancillary services | Medicaid and Managed Medicaid
Disaggregation of Revenue [Line Items]
Other revenues	570	538
Other—Ancillary services | Other Government Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	121,585	116,895
Other—Ancillary services | Commercial Payors
Disaggregation of Revenue [Line Items]
Patient service revenues	54,516	52,425
Other revenues	1,206	1,338
Other—Ancillary services | Other
Disaggregation of Revenue [Line Items]
Other revenues	$ 12,839	$ 9,836