Changes in Goodwill by Reportable Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Mar. 31, 2017
Goodwill [Roll Forward]
Beginning balance	$ 9,407,317	$ 9,294,479	$ 9,294,479
Acquisitions	78,729		447,828
Divestitures	(14,139)		(44,759)
Goodwill impairment charges	(24,198)	(77,000)	(281,415)
Foreign currency and other adjustments	4,761		(8,816)
Ending balance	9,452,470		9,407,317
Goodwill				$ 9,952,761
Accumulated impairment charges				(500,291)
Goodwill, net	9,407,317	9,294,479	9,294,479	9,452,470
U.S. dialysis and related lab services
Goodwill [Roll Forward]
Beginning balance	5,691,587	5,629,183	5,629,183
Acquisitions	46,569		75,295
Divestitures	(14,110)		(12,891)
Ending balance	5,724,046		5,691,587
Goodwill				5,724,046
Accumulated impairment charges				0
Goodwill, net	5,691,587	5,629,183	5,629,183	5,724,046
DMG
Goodwill [Roll Forward]
Beginning balance	3,391,942	3,398,264	3,398,264
Acquisitions	14,989		248,901
Divestitures	(29)		(2,223)
Goodwill impairment charges	0		(253,000)
Ending balance	3,406,902		3,391,942
Goodwill				3,848,671
Accumulated impairment charges				(441,769)
Goodwill, net	3,391,942	3,398,264	3,398,264	3,406,902
Ancillary services and strategic initiatives
Goodwill [Roll Forward]
Beginning balance	323,788	267,032	267,032
Acquisitions	17,171		123,632
Divestitures	0		(29,645)
Goodwill impairment charges	(24,198)		(28,415)
Foreign currency and other adjustments	4,761		(8,816)
Ending balance	321,522		323,788
Goodwill				380,044
Accumulated impairment charges				(58,522)
Goodwill, net	$ 323,788	$ 267,032	$ 267,032	$ 321,522