Acquisitions and Divestitures - Additional Information (Details) $ in Thousands			12 Months Ended
	Jun. 19, 2019 USD ($)	May 01, 2017 USD ($) patient state clinic outpatient_dialysis_center	Dec. 31, 2019 USD ($) clinic	Dec. 31, 2018 USD ($) clinic	Dec. 31, 2017 USD ($) clinic
Business Acquisition [Line Items]
Cash paid to acquire business			$ 100,861	$ 183,156	$ 803,879
Contingent earn-out obligations associated with acquisitions			23,536	1,246
Non-cash gain on acquiring additional ownership in business acquisition				28,152
Proceeds from divestiture of business	$ 4,465,476
Contingent earn-out obligations			33,889
Fair value of contingent earn-out consideration			24,586	2,608	6,388
Other accrued liabilities
Business Acquisition [Line Items]
Fair value of contingent earn-out consideration			6,712
Other long-term liabilities
Business Acquisition [Line Items]
Fair value of contingent earn-out consideration			17,874
Other companies
Business Acquisition [Line Items]
Fair value of contingent earn-out consideration			$ 24,586
Minimum | Other companies | EBITDA or Operating Income Performance Targets or Quality Margins
Business Acquisition [Line Items]
Earn-out consideration payment period			1 year
Maximum | Other companies | EBITDA or Operating Income Performance Targets or Quality Margins
Business Acquisition [Line Items]
Earn-out consideration payment period			5 years
Series of individually immaterial business acquisitions
Business Acquisition [Line Items]
Cash paid to acquire business			$ 98,836	176,161	308,550
Contingent earn-out obligations associated with acquisitions			23,536	1,246	2,692
Deferred Purchase price and liabilities assumed			$ 4,326	$ 34,394	$ 23,748
Amortizable intangible assets acquired, weighted-average estimated useful lives			6 years	6 years	7 years
Goodwill deductible for tax purposes associated with acquisitions			$ 88,517	$ 165,013	$ 237,363
Renal Ventures Limited, LLC
Business Acquisition [Line Items]
Cash paid to acquire business		$ 359,913
Amortizable intangible assets acquired, weighted-average estimated useful lives			5 years
Goodwill deductible for tax purposes associated with acquisitions			$ 298,200
Ownership interest percentage		100.00%
Number of dialysis clinic patients | patient		2,600
Number of states where dialysis centers are located | state		6
Proceeds from divestiture of business		$ 21,219
Business acquisition, transaction costs					$ 11,950
Operating Dialysis Center
Business Acquisition [Line Items]
Number of businesses divested | outpatient_dialysis_center		3
Operating Dialysis Center | Renal Ventures Limited, LLC
Business Acquisition [Line Items]
Number of businesses acquired | clinic		36
Number of businesses divested | outpatient_dialysis_center		3
New Center Under Construction | Renal Ventures Limited, LLC
Business Acquisition [Line Items]
Number of businesses acquired | clinic		1
Number of businesses divested | outpatient_dialysis_center		1
Home Dialysis Clinic | Renal Ventures Limited, LLC
Business Acquisition [Line Items]
Number of businesses acquired | clinic		1
U S Dialysis And Related Lab Services | Series of individually immaterial business acquisitions
Business Acquisition [Line Items]
Number of businesses acquired | clinic			7	18	30
Foreign Dialysis Centers | Series of individually immaterial business acquisitions
Business Acquisition [Line Items]
Number of businesses acquired | clinic			16	28	68