Acquisitions and Other Significant Transactions (Details) | May. 01, 2015USD ($)Community | Jun. 04, 2013USD ($)Child | Oct. 31, 2015USD ($)Community | Feb. 28, 2015USD ($)Community | Aug. 31, 2014USD ($)CommunityUnitEntityPropertyMemberRepresentative | Jul. 31, 2014USD ($)Community | Dec. 31, 2015USD ($)Communityshares | Sep. 30, 2015USD ($) | Jun. 30, 2015USD ($) | Mar. 31, 2015USD ($) | Dec. 31, 2014USD ($)Communityshares | Sep. 30, 2014USD ($) | Jun. 30, 2014USD ($) | Mar. 31, 2014USD ($) | Jun. 30, 2015USD ($)Community | Sep. 30, 2015USD ($) | Dec. 31, 2015USD ($)Communityshares | Dec. 31, 2014USD ($)Community$ / sharesshares | Dec. 31, 2013USD ($)$ / sharesshares | Jul. 30, 2014shares |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Percentage of voting interests acquired | | | | | | 100.00% | | | | | | | | | | | | | | |
Number of communities operated under long-term leases | Community | | | | | | | 546 | | | | 583 | | | | | | 546 | 583 | | |
Aggregate acquisition-date fair value of purchase consideration transferred | | | | | | $ 3,000,000,000 | | | | | | | | | | | | | | |
Amount of mortgage indebtedness assumed | | | | | | $ 1,400,000,000 | | | | | | | | | | | | | | |
Number of underlying communities with which mortgage loans collateralized | Community | | | | | | 179 | | | | | | | | | | | | | | |
Transaction costs of acquisition | | | | | | | | | | | | | | | | | $ 8,252,000 | $ 66,949,000 | $ 3,921,000 | |
Common stock, shares authorized (in shares) | shares | | | | | | | 400,000,000 | | | | 400,000,000 | | | | | | 400,000,000 | 400,000,000 | | 400 |
Number of venture transactions entered by the entity | Unit | | | | | 2 | | | | | | | | | | | | | | | |
Term of master agreement | | | | | 15 years | | | | | | | | | | | | | | | |
Percentage of interest acquired in joint venture (in hundredths) | | | | | 51.00% | | | | | | | | | | | | | | | |
Partners Joint Venture Ownership Percentage (in hundredths) | | | | | 49.00% | | | | | | | | | | | | | | | |
Number of wholly-owned entities contributed to the venture by the entity | Entity | | | | | 8 | | | | | | | | | | | | | | | |
Number of communities owned by the entity | Community | | | | | 8 | | | | | | | | | | | | | | | |
Number of wholly-owned entities contributed to the venture by venture partner | Entity | | | | | 3 | | | | | | | | | | | | | | | |
Number of properties owned by venture partner | Property | | | | | 3 | | | | | | | | | | | | | | | |
Number of communities owned by venture partner | Community | | | | | 2 | | | | | | | | | | | | | | | |
Number of Communities Deconsolidated | Community | | | | | | | | | | | | | | | | | | 10 | | |
Cash contributed to venture by venture partner | | | | | $ 323,500,000 | | | | | | | | | | | | | | | |
Number of members on board | Member | | | | | 6 | | | | | | | | | | | | | | | |
Number of representatives on board | Representative | | | | | 3 | | | | | | | | | | | | | | | |
Number of communities under master lease and security agreement | Community | | | | | 112 | | | | | | | | | | | | | | | |
Number of communities under triple net leases agreement | Community | | | | | 41 | | | | | | | | | | | | | | | |
Number of pools under amended master leases agreement | Unit | | | | | 3 | | | | | | | | | | | | | | | |
Master leases term for Pool one communities | | | | | 14 years | | | | | | | | | | | | | | | |
Master leases term for Pool two communities | | | | | 15 years | | | | | | | | | | | | | | | |
Master leases term for Pool three communities | | | | | 16 years | | | | | | | | | | | | | | | |
Number of extension options | Unit | | | | | 2 | | | | | | | | | | | | | | | |
Term of extension option | | | | | 10 years | | | | | | | | | | | | | | | |
Base rent as per amended master leases agreement | | | | | $ 158,000,000 | | | | | | | | | | | | | | | |
Maximum available reimbursement for capital expenditures by co venturer | | | | | $ 100,000,000 | | | | | | | | | | | | | | | |
Initial lease rate for lessor reimbursements for capital expenditures (in hundredths) | | | | | 7.00% | | | | | | | | | | | | | | | |
Number of communities for which purchase option included in master lease | Community | | | | | 10 | | | | | | | | | | | | | | | |
Maximum aggregate purchase price of communities under purchase option | | | | | $ 60,000,000 | | | | | | | | | | | | | | | |
Number Of Communities With Cancelled Purchase Options | Community | | | | | 49 | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | | | | | | | | | | | | | | 4 | | |
Number of communities with modified term | Community | | | | | 20 | | | | | | | | | | | | | | | |
Extinguishment of Debt, Amount | | | | | | | | | | | | | | | | | | $ 275,900,000 | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Total revenue | | | | | | | | | | | | | | | | | | 5,055,000,000 | 4,853,000,000 | |
Net loss attributable to common shares | | | | | | | | | | | | | | | | | | $ (103,000,000) | $ (424,000,000) | |
Basic and diluted net loss per share attributable to common shares | $ / shares | | | | | | | | | | | | | | | | | | $ (0.59) | $ (2.48) | |
Weighted average shares used in computing basic and diluted net loss per share (in shares) | shares | | | | | | | | | | | | | | | | | | 175,823 | 171,255 | |
Loss on facility lease termination | | | | | | | | | | | | | | | | | $ 76,143,000 | $ 0 | $ 0 | |
Asset impairment | | | | | | | $ 57,941,000 | $ 0 | $ 0 | $ 0 | $ 9,992,000 | $ 0 | $ 0 | $ 0 | | | 57,941,000 | 9,992,000 | 12,891,000 | |
Aggregate selling price | | | | | | | | | | | | | | | | | 82,900,000 | 9,200,000 | | |
Assets Held-for-sale | | | | | | | 110,620,000 | | | | 0 | | | | | | 110,620,000 | 0 | | |
Long-term debt, less current portion | | | | | | | $ 3,459,371,000 | | | | 3,340,971,000 | | | | | | $ 3,459,371,000 | 3,340,971,000 | | |
Communities classified as held for sale | Community | | | | | | | 17 | | | | | | | | | | 17 | | | |
Partners Joint Venture Ownership Percentage | | | | | 49.00% | | | | | | | | | | | | | | | |
Investment in unconsolidated ventures | | | | | | | | | | | | | | | | | $ (69,297,000) | (26,499,000) | (17,172,000) | |
Loss Contingencies [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of adult children of Joan Boice | Child | | 3 | | | | | | | | | | | | | | | | | | |
Attorney fees awarded to plaintiffs' lawyer | | $ 4,100,000 | | | | | | | | | | | | | | | | | | |
Cash deposit made to collateralize the bond | | 20,900,000 | | | | | | | | | | | | | | | | | | |
Stockholders' Equity Note [Abstract] | | | | | | | | | | | | | | | | | | | | |
Stock Issued During Period, Shares, New Issues | shares | | | | | | | | | | | | | | | | | 10,298,506 | | | |
Proceeds from public equity offering, net | | | | | | | | | | | | | | | | | $ 0 | 330,386,000 | 0 | |
Deferred Offering Costs | | | | | | | | | | | $ 400,000 | | | | | | | $ 400,000 | | |
Weighted average interest rate | | | | | | | | | | | 5.50% | | | | | | | 5.50% | | |
Extinguishment of Debt, Amount | | | | | | | | | | | | | | | | | | $ 275,900,000 | | |
Common stock issued in connection with Emeritus acquisition | | | | | | | | | | | | | | | | | | $ 1,648,782,000 | | |
Stock Issued During Period, Shares, Acquisitions | shares | | | | | | | | | | | | | | | | | | 47,584,000 | | |
CCRCs JV [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | 4 | | | | | | | | | | | | | | | |
RIDEA JV [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Percentage of interest acquired in joint venture (in hundredths) | | | | | 20.00% | | | | | | | | | | | | | | | |
Partners Joint Venture Ownership Percentage (in hundredths) | | | | | 80.00% | | | | | | | | | | | | | | | |
Advance from co venturers affiliate | | | | | $ 68,000,000 | | | | | | | | | | | | | | | |
Number of communities contributed by venture partner | Community | | | | | 49 | | | | | | | | | | | | | | | |
Lease restructuring fee payable to co venturer | | | | | $ 34,000,000 | | | | | | | | | | | | | | | |
Period with in which lease restructuring fee payable | | | | | 2 years | | | | | | | | | | | | | | | |
Extinguishment of Debt, Amount | | | | | | | | | | | | | | | | | | $ 68,000,000 | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Partners Joint Venture Ownership Percentage | | | | | 80.00% | | | | | | | | | | | | | | | |
Stockholders' Equity Note [Abstract] | | | | | | | | | | | | | | | | | | | | |
Extinguishment of Debt, Amount | | | | | | | | | | | | | | | | | | 68,000,000 | | |
Minimum [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Weighted average interest rate (in hundredths) | | | | | | 5.49% | | | | | | | | | | | | | | |
Debt maturity period | | | | | | 3 months | | | | | | | | | | | | | | |
Maximum [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Weighted average interest rate (in hundredths) | | | | | | 6.06% | | | | | | | | | | | | | | |
Debt maturity period | | | | | | 33 years | | | | | | | | | | | | | | |
Punitive damages [Member] | | | | | | | | | | | | | | | | | | | | |
Loss Contingencies [Line Items] | | | | | | | | | | | | | | | | | | | | |
Damages to be paid | | 23,000,000 | | | | | | | | | | | | | | | | | | |
Compensatory damages [Member] | | | | | | | | | | | | | | | | | | | | |
Loss Contingencies [Line Items] | | | | | | | | | | | | | | | | | | | | |
Damages to be paid | | $ 250,000 | | | | | | | | | | | | | | | | | | |
Retirement Centers [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | | 3 | | | | | | | | | | | | | | |
Preliminary Allocation of Purchase Price [Abstract] | | | | | | | | | | | | | | | | | | | | |
Goodwill acquired during period | | | | | | | | | | | | | | | | | | 20,499,000 | | |
Assisted Living [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | | 1 | | | | | | | | | | | | | | |
Preliminary Allocation of Purchase Price [Abstract] | | | | | | | | | | | | | | | | | | | | |
Goodwill acquired during period | | | | | | | | | | | | | | | | | | 497,900,000 | | |
Brookdale Ancillary Services [Member] | | | | | | | | | | | | | | | | | | | | |
Preliminary Allocation of Purchase Price [Abstract] | | | | | | | | | | | | | | | | | | | | |
Goodwill acquired during period | | | | | | | | | | | | | | | | | | 126,810,000 | | |
Emeritus [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities operated | Community | | | | | | 493 | | | | | | | | | | | | | | |
Number of communities operated under long-term leases | Community | | | | | | 311 | | | | | | | | | | | | | | |
Transaction costs of acquisition | | | | | | | | | | | | | | | | | | 57,100,000 | | |
Number of communities owned by the entity | Community | | | | | | 182 | | | | | | | | | | | | | | |
Preliminary Allocation of Purchase Price [Abstract] | | | | | | | | | | | | | | | | | | | | |
Cash and cash equivalents | | | | | | | $ 28,000,000 | | | | | | | | | | 28,000,000 | | | |
Property, plant and equipment and leasehold intangibles | | | | | | | 5,506,000,000 | | | | | | | | | | 5,506,000,000 | | | |
Goodwill acquired during period | | | | | | | | | | | | | | | | | | $ 645,000 | | |
Other intangible assets, net | | | | | | | 259,000,000 | | | | | | | | | | 259,000,000 | | | |
Other assets, net | | | | | | | 307,000,000 | | | | | | | | | | 307,000,000 | | | |
Trade Accounts Payable and accrued expenses | | | | | | | (297,000,000) | | | | | | | | | | (297,000,000) | | | |
Long-term debt | | | | | | | (1,516,000,000) | | | | | | | | | | (1,516,000,000) | | | |
Capital and Financing Lease obligations | | | | | | | (2,692,000,000) | | | | | | | | | | (2,692,000,000) | | | |
Deferred tax liability | | | | | | | (339,000,000) | | | | | | | | | | (339,000,000) | | | |
Other liabilities | | | | | | | (251,000,000) | | | | | | | | | | (251,000,000) | | | |
Noncontrolling interest | | | | | | | (1,000,000) | | | | | | | | | | (1,000,000) | | | |
Fair value of Brookdale common stock issued | | | | | | | $ 1,649,000,000 | | | | | | | | | | $ 1,649,000,000 | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Goodwill, Purchase Accounting Adjustments | | | | | | | | | | | | | | | | $ 5,900,000 | | | | |
Acquisition of Communities [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | | 4 | | | | | | | | | | | | | | |
Aggregate purchase price | | | | | | $ 51,400,000 | | | | | | | | | | | | | | |
Acquisition purchase price amount financed | | | | | | $ 17,000,000 | | | | | | | | | | | | | | |
Number of communities securing acquisition financing | Community | | | | | | 3 | | | | | | | | | | | | | | |
Acquired property plant and equipment [Member] | Minimum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 5.50% | | | | | | | | | | | | | | |
Acquired property plant and equipment [Member] | Maximum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 9.75% | | | | | | | | | | | | | | |
Acquired capital and financing lease obligations [Member] | Minimum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 6.00% | | | | | | | | | | | | | | |
Acquired capital and financing lease obligations [Member] | Maximum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 10.75% | | | | | | | | | | | | | | |
Acquired long-term debt obligations [Member] | Minimum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 3.00% | | | | | | | | | | | | | | |
Acquired long-term debt obligations [Member] | Maximum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | | | 7.00% | | | | | | | | | | | | | | |
SellerFinanced Debt [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
LoanTerm | | | | | | | | | | | | | | | | | 5 years | | | |
Seller financing fixed rate | | | | | | | 8.00% | | | | | | | | | | 8.00% | | | |
Principal | | | | | | | $ 20,000,000 | | | | | | | | | | $ 20,000,000 | | | |
Acquisition of Venture Interest [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Partners Joint Venture Ownership Percentage (in hundredths) | | | | | | | | | 10.00% | | | | | | 10.00% | | | | | |
Number of communities purchased or sold | Community | | | | | | | | | | | | | | | 35 | | | | | |
Aggregate purchase price | | | | | | | | | | | | | | | $ 847,000,000 | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Partners Joint Venture Ownership Percentage | | | | | | | | | 10.00% | | | | | | 10.00% | | | | | |
Investment in unconsolidated ventures | | | | | | | | | | | | | | | $ 30,300,000 | | | | | |
February 2015 acquisition of 15 communities [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | 15 | | | | | | | | | | | | | | | | |
Aggregate purchase price | | | | $ 268,600,000 | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value of Assets Acquired | | | | 187,200,000 | | | | | | | | | | | | | | | | |
Reversal of deferred lease liability | | | | 5,300,000 | | | | | | | | | | | | | | | | |
Loss on facility lease termination | | | | $ 76,100,000 | | | | | | | | | | | | | | | | |
February 2015 acquisition of 15 communities [Member] | Minimum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | 6.25% | | | | | | | | | | | | | | | | |
February 2015 acquisition of 15 communities [Member] | Maximum [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Fair Value Inputs, Cap Rate | | | | 8.75% | | | | | | | | | | | | | | | | |
5 Communities acquired in October 2015 [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | 5 | | | | | | | | | | | | | | | | | |
Aggregate purchase price | | | $ 78,400,000 | | | | | | | | | | | | | | | | | |
Communities sold during 2015 [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | | | | | | | | | | | | | | | | | 17 | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Asset impairment | | | | | | | | | | | | | | | | | $ 18,400,000 | | | |
Aggregate selling price | | | | | | | | | | | | | | | | | 82,900,000 | | | |
HCP Community Acquisitions [Member] | | | | | | | | | | | | | | | | | | | | |
Business Acquisition [Line Items] | | | | | | | | | | | | | | | | | | | | |
Number of communities purchased or sold | Community | 1 | | | | | | | | | | | | | | | | | 9 | | |
Aggregate purchase price | $ 8,600,000 | | | | | | | | | | | | | | | | | $ 60,000,000 | | |
Disposal Group, Held-for-sale, Not Discontinued Operations [Member] | | | | | | | | | | | | | | | | | | | | |
Pro-forma consolidated operational data [Abstract] | | | | | | | | | | | | | | | | | | | | |
Asset impairment | | | | | | | | | | | | | | | | | 15,172,000 | 0 | 0 | |
Assets Held-for-sale | | | | | | | 110,620,000 | | | | $ 0 | | | | | | 110,620,000 | $ 0 | $ 0 | |
Long-term debt, less current portion | | | | | | | $ 60,800,000 | | | | | | | | | | $ 60,800,000 | | | |