Segment Information (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) segment	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			5
Revenue	$ 1,120,062	$ 1,177,988	$ 3,462,496	$ 3,581,226
Segment Operating Income	251,631	290,376	830,217	962,762
General and administrative (including non-cash stock-based compensation expense)	57,309	63,779	194,333	196,429
Transaction costs	1,487	1,992	8,805	12,924
Facility lease expense	70,392	84,437	232,752	257,934
Depreciation and amortization	110,980	117,649	341,351	366,023
Goodwill and asset impairment	5,500	368,551	451,966	390,816
Loss on facility lease termination and modification, net	2,337	4,938	148,804	11,306
Income (loss) from operations	3,626	(350,970)	(547,794)	(272,670)
Total assets	6,494,637		$ 6,494,637		$ 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	144,631	161,986	$ 462,321	496,854
Segment Operating Income	57,106	65,907	186,662	207,206
Total assets	1,295,001		1,295,001		1,266,076
Operating Segments [Member] \| Assisted Living
Segment Reporting Information [Line Items]
Revenue	483,125	542,227	1,537,432	1,680,194
Segment Operating Income	144,701	173,576	490,976	577,936
Total assets	3,775,584		3,775,584		4,535,114
Operating Segments [Member] \| CCRCs Rental
Segment Reporting Information [Line Items]
Revenue	104,147	108,075	314,012	364,075
Segment Operating Income	21,809	22,932	70,291	82,591
Total assets	716,815		716,815		667,234
Operating Segments [Member] \| Brookdale Ancillary Services
Segment Reporting Information [Line Items]
Revenue	108,276	110,604	328,649	332,766
Segment Operating Income	9,487	9,823	28,008	38,555
Total assets	254,781		254,781		257,257
Operating Segments [Member] \| Management Services
Segment Reporting Information [Line Items]
Revenue	279,883	255,096	820,082	707,337
Segment Operating Income	18,528	$ 18,138	54,280	$ 56,474
Total assets	$ 452,456		$ 452,456		$ 949,768

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