Acquisitions (Details) (USD $)	3 Months Ended		12 Months Ended	1 Months Ended	0 Months Ended	1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014 Community	Feb. 28, 2015 Community	May 01, 2015 Community	Jul. 31, 2014 Community
Schedule of Acquisitions and Disposals [Line Items]
Loss on facility lease termination	$ 76,143,000	$ 0
Goodwill, Purchase Accounting Adjustments	1,800,000
Pro-forma consolidated operational data [Abstract]
Total revenue		1,269,000,000
Net loss attributable to common shares		(15,000,000)
Basic and diluted net loss per share attributable to common shares		$ (0.09)
Weighted average shares used in computing basic and diluted net loss per share (in shares)		172,062,000
Transaction costs	6,742,000	10,844,000
January 1, 2015 purchase of communities under HCP Purchase Option [Member]
Schedule of Acquisitions and Disposals [Line Items]
Number of communities purchased or sold	8
Aggregate purchase price	51,400,000
Communities agreed to purchase under HCP Master Lease Purchase Option [Member]
Schedule of Acquisitions and Disposals [Line Items]
Number of communities purchased or sold			9
Aggregate purchase price			60,000,000
February 2015 acquisition of 15 communities [Member]
Schedule of Acquisitions and Disposals [Line Items]
Number of communities purchased or sold				15
Aggregate purchase price				268,600,000
Loss on facility lease termination				76,100,000
Reversal of deferred lease liability				5,300,000
Fair Value of Assets Acquired				187,200,000
SellerFinanced Debt [Member]
Schedule of Acquisitions and Disposals [Line Items]
Principal	20,000,000
LoanTerm	5 years
Seller financing fixed rate	8.00%
May 1, 2015 purchase of community under HCP Purchase Option [Member]
Schedule of Acquisitions and Disposals [Line Items]
Number of communities purchased or sold					1
Aggregate purchase price					8,600,000
Emeritus [Member]
Schedule of Acquisitions and Disposals [Line Items]
Number of communities operated						493
Number of communities operated under long-term leases						311
Number of communities owned by the entity						182
Stock Issued During Period, Shares, Acquisitions						47,600,000
Amount of mortgage indebtedness assumed						1,400,000,000
Goodwill, Purchase Accounting Adjustments	1,800,000
Aggregate acquisition-date fair value of purchase consideration transferred						3,000,000,000
Fair value of Brookdale common stock issued						1,600,000,000
Pro-forma consolidated operational data [Abstract]
Transaction costs		$ 10,400,000