Segment Reporting - Summary of Segment Net Revenues, Segment Operating Income (Loss) and Reconciliation of Segment Income to Consolidated Income from Continuing Operations Before Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Segment Reporting Information [Line Items]
Other revenues			$ 555,175	$ 565,206	$ 433,430
Total revenues			12,815,550	12,140,147	11,609,894
Operating Income (Loss)			2,090,483	1,602,784	1,339,062
Corporate administrative support			(113,181)	(163,047)	(129,669)
Debt expense			(470,469)	(398,551)	(357,019)
Debt prepayment, extinguishment and modification costs	$ (10,081)	$ (9,732)	(19,813)	(7,962)	0
Other loss, net			(69,808)	(19,177)	(15,765)
Income from continuing operations before income taxes			1,530,393	1,177,094	966,278
Segment Reporting Information footnote:
Equity investment income (loss) from equity method investments in nonconsolidated dialysis partnerships.			26,189	27,864	26,520
Patient care costs			8,598,521	8,319,717	8,209,553
General and administrative			1,538,341	1,473,984	1,355,197
Operating expenses and charges			10,725,067	10,537,363	10,270,832
Depreciation and amortization			723,860	745,443	732,602
Property and equipment, net of accumulated depreciation			2,940,916	3,073,533
Other - Ancillary services
Segment Reporting Information footnote:
Depreciation and amortization			62,679	49,769	41,653
Operating Segments
Segment Reporting Information [Line Items]
Total revenues			12,901,207	12,236,221	11,701,135
Operating Income (Loss)			2,203,664	1,765,831	1,468,731
Operating Segments | U.S. dialysis
Segment Reporting Information [Line Items]
Operating Income (Loss)			2,121,007	1,774,578	1,565,310
Segment Reporting Information footnote:
Patient care costs			7,497,576	7,394,640	7,334,415
General and administrative			1,173,990	1,102,072	1,037,552
Segment Reporting, Other Segment Item, Amount			(63,037)	(29,966)	(28,417)
Operating expenses and charges			9,269,710	9,162,420	9,034,499
Depreciation and amortization			661,181	695,674	690,949
Operating Segments | Other - Ancillary services
Segment Reporting Information [Line Items]
Operating Income (Loss)			82,657	(8,747)	(96,579)
Segment Reporting Information footnote:
Equity investment income (loss) from equity method investments in nonconsolidated dialysis partnerships.			(1,701)	(2,103)	(1,898)
Operating expenses and charges			1,427,833	1,307,970	1,197,905
Operating Segments | U S Dialysis And Related Lab Services with Intersegment
Segment Reporting Information [Line Items]
Dialysis patient service revenues			11,366,361	10,911,747	10,575,372
Total revenues			11,390,717	10,936,998	10,599,809
Operating Segments | U S Dialysis And Related Lab Services with Intersegment | External Sources
Segment Reporting Information [Line Items]
Dialysis patient service revenues			11,294,614	10,823,525	10,488,327
Other revenues			24,356	25,251	24,447
Operating Segments | U S Dialysis And Related Lab Services with Intersegment | Intersubsegment Eliminations
Segment Reporting Information [Line Items]
Dialysis patient service revenues			71,747	88,222	87,045
Other revenues			0	0	(10)
Operating Segments | Other Operating Segments with Intersegment
Segment Reporting Information [Line Items]
Dialysis patient service revenues			965,761	751,416	688,137
Other revenues			530,819	539,955	408,983
Total revenues			1,510,490	1,299,223	1,101,326
Operating Segments | Other Operating Segments with Intersegment | Intersubsegment Eliminations
Segment Reporting Information [Line Items]
Dialysis patient service revenues			13,910	7,852	4,206
Intersegment Elimination
Segment Reporting Information [Line Items]
Total revenues			$ (85,657)	$ (96,074)	$ (91,241)