Concentration of Credit Risk (Details) $ in Thousands		3 Months Ended		9 Months Ended		12 Months Ended
		Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) item	Sep. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Concentration of risk
Number of RIDEA joint ventures | item				3
Balance Sheets:
Real estate and other property, net		$ 12,249,349		$ 12,249,349		$ 10,886,887
Cash and cash equivalents		120,498	$ 83,531	120,498	$ 83,531	183,810	$ 300,556
Goodwill, intangible and other assets, net		883,333		883,333		940,172
Total assets	[1]	22,192,973		22,192,973		21,369,940
Accounts payable, accrued liabilities and other		401,838		401,838		432,934
Total equity		10,460,457	11,036,174	10,460,457	11,036,174	10,997,099	$ 10,931,134
Total liabilities and equity		22,192,973		22,192,973		21,369,940
Income Statements:
Revenues		657,953	596,638	1,876,276	1,662,751
Operating, general and administrative expense		(173,515)	(99,599)	(441,888)	(254,173)
Depreciation and amortization expense		(134,704)	(122,975)	(369,629)	(343,496)
Interest expense		(122,157)	(111,275)	(357,569)	(324,755)
Other income, net		(974)	3,111	18,130	5,750
Loss on disposal of assets		52		6,377
Income tax (benefit) expense		(1,980)	55	(6,620)	2,840
Income (loss) from continuing operations		117,954	251,059	48,199	707,215
Income (loss) from discontinued operations, net of taxes					29,746
Net income		117,954	251,059	$ 48,199	736,961
Brookdale Senior Living | Maximum
Income Statements:
Management fees as percentage of gross revenues				5.00%
Brookdale Senior Living | Minimum
Income Statements:
Management fees as percentage of gross revenues				4.50%
Brookdale Senior Living | CCRC JV
Concentration of risk
Number of RIDEA joint ventures | item				2
HCRMC
Balance Sheets:
Real estate and other property, net		2,641,100		$ 2,641,100		2,934,400
Cash and cash equivalents		150,500		150,500		127,900
Goodwill, intangible and other assets, net		4,820,600		4,820,600		4,621,700
Total assets		7,612,200		7,612,200		7,684,000
Debt and financing obligations		6,049,300		6,049,300		6,108,300
Accounts payable, accrued liabilities and other		975,300		975,300		932,700
Total equity		587,600		587,600		643,000
Total liabilities and equity		7,612,200		7,612,200		$ 7,684,000
Income Statements:
Revenues		1,009,600	1,026,000	3,091,100	3,101,800
Operating, general and administrative expense		(885,700)	(881,300)	(2,667,800)	(2,676,500)
Depreciation and amortization expense		(33,300)	(35,700)	(104,600)	(106,000)
Interest expense		(119,700)	(101,600)	(339,900)	(305,900)
Other income, net		2,600	800	7,500	5,400
Loss on disposal of assets		(76,000)	(1,400)	(76,000)	(1,400)
(Loss) income from continuing operations before income tax expense		(102,500)	6,800	(89,700)	17,400
Income tax (benefit) expense		(44,400)	3,100	(38,800)	7,400
Income (loss) from continuing operations		(58,100)	3,700	(50,900)	10,000
Income (loss) from discontinued operations, net of taxes		2,100	2,000	(3,900)	(6,800)
Net income		(56,000)	5,700	(54,800)	3,200
Senior housing
Income Statements:
Operating, general and administrative expense		(111,167)	(43,017)	(263,191)	(92,388)
Post-acute/skilled
Income Statements:
Operating, general and administrative expense		$ (531)	$ (534)	$ (1,602)	$ (1,599)
Management and Accounting Services | Brookdale Senior Living | Maximum
Income Statements:
Management Agreement Number of Renewals | item				4
Management and Accounting Services | Brookdale Senior Living | Minimum
Income Statements:
Management Agreement Number of Renewals | item				3
Management and Accounting Services | Senior housing | Brookdale Senior Living
Income Statements:
Number of Facilities | item				106
Management agreement renewal term (in years)				5 years
Management and Accounting Services | Senior housing | Brookdale Senior Living | Maximum
Income Statements:
Management agreement term (in years)				15 years
Management and Accounting Services | Senior housing | Brookdale Senior Living | Minimum
Income Statements:
Management agreement term (in years)				10 years
Assets | Post-acute/skilled | HCRMC
Concentration of risk
Concentration risk (as a percent)				82.00%		82.00%
Assets | Tenants and Operators | Brookdale Senior Living
Concentration of risk
Concentration risk (as a percent)				12.00%		13.00%
Assets | Tenants and Operators | HCRMC
Concentration of risk
Concentration risk (as a percent)				28.00%		31.00%
Assets | Tenants and Operators | Senior housing | Brookdale Senior Living
Concentration of risk
Concentration risk (as a percent)				28.00%		36.00%
Assets | Tenants and Operators | Senior housing | HCRMC
Concentration of risk
Concentration risk (as a percent)				10.00%		11.00%
Revenue | Post-acute/skilled | HCRMC
Concentration of risk
Concentration risk (as a percent)				79.00%	86.00%
Revenue | Tenants and Operators | Brookdale Senior Living
Concentration of risk
Concentration risk (as a percent)		9.00%	13.00%	10.00%	15.00%
Revenue | Tenants and Operators | HCRMC
Concentration of risk
Concentration risk (as a percent)		21.00%	25.00%	23.00%	27.00%
Revenue | Tenants and Operators | Senior housing | Brookdale Senior Living
Concentration of risk
Concentration risk (as a percent)		21.00%	32.00%	24.00%	40.00%
Revenue | Tenants and Operators | Senior housing | HCRMC
Concentration of risk
Concentration risk (as a percent)		7.00%	7.00%	8.00%	9.00%
Revenue | Tenants and Operators | Post-acute/skilled | HCRMC
Concentration of risk
Concentration risk (as a percent)		81.00%	86.00%

[1] HCP, Inc.’s consolidated total assets at September 30, 2015 and December 31, 2014 include assets of certain variable interest entities (“VIEs”) that can only be used to settle the liabilities of those VIEs. Total assets at September 30, 2015 include VIE assets as follows: buildings and improvements $770 million; land $125 million; accumulated depreciation and amortization $128 million; accounts receivable $15 million; cash $61 million; intangible assets, net $31 million; and other assets, net $13 million. Total assets at December 31, 2014 include VIE assets as follows: buildings and improvements $677 million; land $113 million; accumulated depreciation and amortization $111 million; accounts receivable $5 million; cash $42 million; and other assets, net $23 million. See Note 18 to the Consolidated Financial Statements for additional information.