Segment Information (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) segment	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	5
Revenue	$ 1,042,044	$ 1,187,234
Segment Operating Income	239,128	292,622
General and administrative expense (including non-cash stock-based compensation expense)	56,311	81,435
Facility lease expense	68,668	80,400
Facility operating lease expense	73,293
Depreciation and amortization	96,888	114,255
Goodwill and asset impairment	391	430,363
Loss on facility lease termination and modification, net	209	0
Income (loss) from operations	16,661	(413,831)
Total assets	7,630,773		$ 6,467,260
Operating Segments \| Independent Living
Segment Reporting Information [Line Items]
Revenue	135,694	158,397
Segment Operating Income	52,876	64,422
Total assets	1,486,073		1,104,774
Operating Segments \| Assisted Living and Memory Care
Segment Reporting Information [Line Items]
Revenue	458,526	532,280
Segment Operating Income	140,699	176,538
Total assets	4,359,760		3,684,170
Operating Segments \| CCRCs Rental
Segment Reporting Information [Line Items]
Revenue	103,727	105,069
Segment Operating Income	21,637	24,663
Total assets	801,120		707,819
Operating Segments \| Health Care Services
Segment Reporting Information [Line Items]
Revenue	111,532	110,520
Segment Operating Income	8,173	8,318
Total assets	275,130		254,950
Operating Segments \| Management Services
Segment Reporting Information [Line Items]
Revenue	232,565	280,968
Segment Operating Income	15,743	$ 18,681
Total assets	$ 708,690		$ 715,547

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