Segment Information (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) segment	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			5
Revenue	$ 1,155,200	$ 1,186,472	$ 2,342,434	$ 2,403,238
Segment Operating Income	285,964	314,107	578,586	672,386
General and administrative (including non-cash stock-based compensation expense)	60,314	67,090	137,024	132,650
Transaction costs	2,593	3,339	7,318	10,932
Facility lease expense	81,960	84,690	162,360	173,497
Depreciation and amortization	116,116	120,887	230,371	248,374
Goodwill and asset impairment	16,103	1,559	446,466	22,265
Loss on facility lease termination and modification	146,467	6,368	146,467	6,368
Income (loss) from operations	(137,589)	30,174	(551,420)	78,300
Total assets	6,729,647		$ 6,729,647		$ 7,675,449
Retirement Centers
Segment Reporting Information [Line Items]
Age of residential tenant			75 years
Operating Segments [Member] \| Retirement Centers
Segment Reporting Information [Line Items]
Revenue	159,293	162,248	$ 317,690	334,868
Segment Operating Income	65,134	67,297	129,556	141,299
Total assets	1,298,989		1,298,989		1,266,076
Operating Segments [Member] \| Assisted Living
Segment Reporting Information [Line Items]
Revenue	522,027	547,430	1,054,307	1,137,967
Segment Operating Income	169,737	186,921	346,275	404,360
Total assets	3,957,957		3,957,957		4,535,114
Operating Segments [Member] \| CCRCs Rental
Segment Reporting Information [Line Items]
Revenue	104,796	114,202	209,865	256,000
Segment Operating Income	23,819	24,344	48,482	59,659
Total assets	723,655		723,655		667,234
Operating Segments [Member] \| Brookdale Ancillary Services
Segment Reporting Information [Line Items]
Revenue	109,853	110,190	220,373	222,162
Segment Operating Income	10,203	13,103	18,521	28,732
Total assets	244,692		244,692		257,257
Operating Segments [Member] \| Management Services
Segment Reporting Information [Line Items]
Revenue	259,231	252,402	540,199	452,241
Segment Operating Income	17,071	$ 22,442	35,752	$ 38,336
Total assets	$ 504,354		$ 504,354		$ 949,768

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