Segment Information (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment									5
Segment Reporting Information [Line Items]
Revenues	$ 1,165,890	$ 1,177,988	$ 1,186,472	$ 1,216,766	$ 1,208,868	$ 1,246,126	$ 1,258,830	$ 1,263,156	$ 4,747,116	$ 4,976,980	$ 4,960,608
Segment Operating Income									1,253,830	1,439,981	1,448,448
General and administrative (including non-cash stock-based compensation expense)									255,446	313,409	370,579
Transaction costs									22,573	3,990	8,252
Facility lease expense									339,721	373,635	367,574
Depreciation and amortization									482,077	520,402	733,165
Goodwill and asset impairment	18,966	368,551	1,559	20,706	221,877	19,111	4,152	3,375	409,782	248,515	57,941
Loss on facility lease termination									14,276	11,113	76,143
Income (loss) from operations	2,625	(350,970)	$ 30,174	$ 48,126	(178,369)	$ 47,645	$ 58,287	$ 41,354	(270,045)	(31,083)	(165,206)
Total interest expense									326,154	385,617	388,764
Total expenditures for property, plan and equipment, and leasehold improvements									221,476	300,113	448,682
Assets	7,675,449				9,217,687				$ 7,675,449	9,217,687
Retirement Centers
Segment Reporting Information [Line Items]
Age of resident, minimum									75 years
Brookdale Ancillary Services
Segment Reporting Information [Line Items]
Goodwill and asset impairment		$ 13,700
Operating segments | Retirement Centers
Segment Reporting Information [Line Items]
Revenues									$ 654,196	679,503	657,940
Segment Operating Income									271,417	294,530	285,257
Facility lease expense									117,131	120,272	114,738
Depreciation and amortization									95,226	94,049	104,063
Goodwill and asset impairment									2,968	31,384	209
Total interest expense									55,436	56,827	58,397
Total expenditures for property, plan and equipment, and leasehold improvements									47,309	59,978	161,986
Assets	1,266,076				1,452,546				1,266,076	1,452,546
Operating segments | Assisted Living
Segment Reporting Information [Line Items]
Revenues									2,210,688	2,419,459	2,445,457
Segment Operating Income									749,058	876,817	877,303
Facility lease expense									185,971	193,670	197,452
Depreciation and amortization									290,344	308,639	489,933
Goodwill and asset impairment									342,788	132,389	46,179
Total interest expense									207,861	249,449	250,116
Total expenditures for property, plan and equipment, and leasehold improvements									119,717	156,732	220,893
Assets	4,535,114				5,831,434				4,535,114	5,831,434
Operating segments | CCRCs-Rental
Segment Reporting Information [Line Items]
Revenues									468,994	592,826	604,572
Segment Operating Income									106,162	133,409	150,495
Facility lease expense									29,464	51,727	47,937
Depreciation and amortization									44,294	66,431	87,754
Goodwill and asset impairment									18,083	46,329	10,654
Total interest expense									27,665	39,824	39,502
Total expenditures for property, plan and equipment, and leasehold improvements									24,297	37,800	54,864
Assets	667,234				935,389				667,234	935,389
Operating segments | Brookdale Ancillary Services
Segment Reporting Information [Line Items]
Revenues									446,262	476,833	469,158
Segment Operating Income									51,348	64,463	75,210
Facility lease expense									0	0	0
Depreciation and amortization									3,723	4,075	7,451
Goodwill and asset impairment									14,599	1,596	899
Total interest expense									892	1,461	1,354
Total expenditures for property, plan and equipment, and leasehold improvements									755	1,576	4,061
Assets	257,257				280,530				257,257	280,530
Operating segments | Corporate and Management Services
Segment Reporting Information [Line Items]
Revenues									966,976	808,359	783,481
Segment Operating Income									75,845	70,762	60,183
Facility lease expense									7,155	7,966	7,447
Depreciation and amortization									48,490	47,208	43,964
Goodwill and asset impairment									31,344	36,817	0
Total interest expense									34,300	38,056	39,395
Total expenditures for property, plan and equipment, and leasehold improvements									29,398	44,027	$ 6,878
Assets	$ 949,768				$ 717,788				$ 949,768	$ 717,788