Other Acquisition Activities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Goodwill	$ 2,669,810	$ 997,597	$ 992,102
Acquisition Centerre
Business Acquisition [Line Items]
Accounts receivable	28,525
Property and equipment	15,122
Goodwill	265,737
Identifiable intangible assets	23,512
Other assets	21,135
Deferred income taxes and other liabilities	174,766
Total purchase price, net of cash received	179,265
Home-based primary care acquisition
Business Acquisition [Line Items]
Accounts receivable	1,410
Property and equipment	47
Goodwill	9,991
Identifiable intangible assets	2,112
Deferred income taxes and other liabilities	1,408
Total purchase price, net of cash received	12,152
Home health acquisition
Business Acquisition [Line Items]
Goodwill	155
Identifiable intangible assets	1,845
Total purchase price, net of cash received	2,000
Other Acquisitions
Business Acquisition [Line Items]
Goodwill	5,980	104
Deferred income taxes and other liabilities	5,980
Deferred income taxes and other liabilities		(328)
Total purchase price, net of cash received		432
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Accounts receivable	29,935		24,696
Property and equipment	15,169	22,871	94,508
Goodwill	281,863	1,087	97,571
Identifiable intangible assets	27,469	2,590	30,414
Other assets	21,135		5,970
Other assets		(2,280)
Deferred income taxes and other liabilities	182,154	132	28,840
Total purchase price, net of cash received	$ 193,417	24,136	224,319
Home health and hospice acquisitions
Business Acquisition [Line Items]
Accounts receivable			22,470
Property and equipment			2,697
Goodwill		983	89,710
Identifiable intangible assets			16,775
Other assets			4,587
Deferred income taxes and other liabilities		833	26,957
Total purchase price, net of cash received		150	109,282
Acquisition of previously leased real estate
Business Acquisition [Line Items]
Property and equipment		22,871	91,268
Identifiable intangible assets		2,590	5,053
Other assets		(2,280)
Deferred income taxes and other liabilities		(373)
Total purchase price, net of cash received		$ 23,554	96,321
Hospital Rehabilitation Services
Business Acquisition [Line Items]
Accounts receivable			2,226
Property and equipment			53
Goodwill			5,315
Identifiable intangible assets			6,622
Other assets			1,383
Deferred income taxes and other liabilities			1,840
Total purchase price, net of cash received			13,759
Hospital acquisition
Business Acquisition [Line Items]
Property and equipment			490
Goodwill			2,546
Identifiable intangible assets			1,964
Deferred income taxes and other liabilities			43
Total purchase price, net of cash received			$ 4,957