Segment Information (Details) $ in Thousands		3 Months Ended								12 Months Ended
		Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) Segment	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Segment Information [Abstract]
Number of reportable segments | Segment										5
Segment Reporting Information [Line Items]
Revenues		$ 1,235,702	$ 1,238,841	$ 1,238,184	$ 1,247,881	$ 1,252,103	$ 1,083,935	$ 748,393	$ 747,275	$ 4,960,608	$ 3,831,706	$ 2,891,966
Segment operating income										1,448,448	1,133,168	874,213
General and administrative (including non-cash stock-based compensation expense)										370,579	280,267	180,627
Transaction costs										8,252	66,949	3,921
Facility lease expense										367,574	323,830	276,729
Depreciation and amortization										733,165	537,035	268,757
Asset impairment		57,941	0	0	0	9,992	0	0	0	57,941	9,992	12,891
Loss on facility lease termination										76,143	0	0
Income (loss) from operations		(8,873)	$ 3,663	$ (43,123)	$ (116,873)	(74,513)	$ (73,197)	$ 30,657	$ 32,148	(165,206)	(84,905)	131,288
Total interest expense										388,764	248,188	137,399
Total expenditures for property, plan and equipment, and leasehold improvements										448,682	304,245	257,527
Assets by segment		10,048,564				10,417,461				10,048,564	10,417,461
Retirement Centers [Member]
Segment Reporting Information [Line Items]
Revenues	[1]									657,940	582,312	526,284
Segment operating income	[2]									285,257	248,883	222,282
Facility lease expense										114,738	98,321	91,258
Depreciation and amortization										104,063	86,188	64,353
Total interest expense										58,397	41,906	31,286
Total expenditures for property, plan and equipment, and leasehold improvements										161,986	76,285	63,519
Assets by segment		1,556,169				1,600,007				1,556,169	1,600,007
Assisted Living [Member]
Segment Reporting Information [Line Items]
Revenues	[1]									2,445,457	1,685,563	1,051,868
Segment operating income	[2]									877,303	608,489	389,678
Facility lease expense										197,452	162,575	123,980
Depreciation and amortization										489,933	317,918	85,337
Total interest expense										250,116	140,001	51,410
Total expenditures for property, plan and equipment, and leasehold improvements										220,893	107,037	95,829
Assets by segment		6,354,415				6,577,821				6,354,415	6,577,821
CCRCs Rental [Member]
Segment Reporting Information [Line Items]
Revenues	[1]									604,572	493,173	396,975
Segment operating income	[2]									150,495	121,661	109,026
Facility lease expense										47,937	51,523	48,809
Depreciation and amortization										87,754	60,175	30,957
Total interest expense										39,502	28,418	17,512
Total expenditures for property, plan and equipment, and leasehold improvements										54,864	42,412	27,134
Assets by segment		1,037,384				1,027,854				1,037,384	1,027,854
CCRCs Entry Fee [Member]
Segment Reporting Information [Line Items]
Revenues	[1]									0	202,414	297,756
Segment operating income	[2]									0	48,433	76,393
Facility lease expense										0	4,362	7,470
Depreciation and amortization										0	37,524	55,842
Total interest expense										0	7,530	11,911
Total expenditures for property, plan and equipment, and leasehold improvements										0	36,575	43,019
Brookdale Ancillary Services [Member]
Segment Reporting Information [Line Items]
Revenues	[1]									469,158	337,835	242,150
Segment operating income	[2]									75,210	63,463	45,709
Facility lease expense										0	890	0
Depreciation and amortization										7,451	4,764	3,023
Total interest expense										1,354	823	0
Total expenditures for property, plan and equipment, and leasehold improvements										4,061	1,805	1,855
Assets by segment		292,540				275,618				292,540	275,618
Management Services [Member]
Segment Reporting Information [Line Items]
Revenues	[1],[3]									783,481	530,409	376,933
Segment operating income	[2]									60,183	42,239	31,125
Facility lease expense										7,447	6,159	5,212
Depreciation and amortization										43,964	30,466	29,245
Total interest expense										39,395	29,510	25,280
Total expenditures for property, plan and equipment, and leasehold improvements										6,878	40,131	$ 26,171
Assets by segment		$ 808,056				$ 936,161				$ 808,056	$ 936,161

[1] All revenue is earned from external third parties in the United States.

[2] Segment operating income is defined as segment revenues less segment operating expenses (excluding depreciation and amortization).

[3] Management services segment revenue includes reimbursements for which the Company is the primary obligor of costs incurred on behalf of managed communities.