Concentration of Credit Risk (Details) $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2016 USD ($) item	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Concentration of risk
Number of RIDEA joint ventures | item		4
Balance Sheets:
Real estate and other property, net		$ 12,065,135		$ 11,994,703
Cash and cash equivalents		94,665	$ 137,170	346,500	$ 183,810
Goodwill, intangible and other assets, net		817,279		802,273
Total assets	[1]	21,199,927		21,449,849
Accounts payable, accrued liabilities and other		433,144		436,239
Total equity		9,630,325	10,555,646	9,746,317	$ 10,997,099
Total liabilities and equity		21,199,927		21,449,849
Income Statements:
Revenues		640,782	610,791
Operating, general and administrative expense		(176,955)	(132,031)
Depreciation and amortization expense		(141,322)	(114,522)
Interest expense		(122,062)	(116,780)
Other income, net		1,222	7,988
Loss on disposal of assets			6,264
Income taxes		(53,038)	77
Net income (loss)		$ 119,745	(237,503)
Brookdale JV | Minimum
Income Statements:
Management fees as percentage of gross revenues		4.50%
Brookdale JV | Maximum
Income Statements:
Management fees as percentage of gross revenues		5.00%
HCRMC
Balance Sheets:
Real estate and other property, net		$ 2,611,800		2,628,500
Cash and cash equivalents		173,800		125,000
Goodwill, intangible and other assets, net		4,526,900		4,598,300
Total assets		7,312,500		7,351,800
Debt and financing obligations		5,783,800		5,836,400
Accounts payable, accrued liabilities and other		1,006,700		982,900
Total equity		522,000		532,500
Total liabilities and equity		7,312,500		$ 7,351,800
Income Statements:
Revenues		984,500	1,054,000
Operating, general and administrative expense		(857,200)	(897,900)
Depreciation and amortization expense		(32,500)	(35,900)
Interest expense		(115,100)	(100,300)
Other income, net		3,500	2,800
Loss on disposal of assets		3,300
(Loss) income from continuing operations before income tax expense		(13,500)	22,700
Income taxes		2,900	(10,100)
(Loss) income from continuing operations		(10,600)	12,600
Income from discontinued operations, net of taxes		100	1,100
Net income (loss)		(10,500)	13,700
Senior housing
Income Statements:
Operating, general and administrative expense		$ (116,136)	(75,510)
Senior housing | CCRC JV
Concentration of risk
Number of RIDEA joint ventures | item		2
Senior housing | Management and Accounting Services | Brookdale JV
Concentration of risk
Number of RIDEA joint ventures | item		15
Investments in Joint Ventures Senior Housing Facilities Number | item		108
Post-acute/skilled
Income Statements:
Operating, general and administrative expense		$ (564)	$ (533)
Management and Accounting Services | Brookdale JV | Minimum
Income Statements:
Management Agreement Number of Renewals | item		3
Management and Accounting Services | Brookdale JV | Maximum
Income Statements:
Management Agreement Number of Renewals | item		4
Management and Accounting Services | Senior housing | Brookdale JV
Income Statements:
Management agreement renewal term (in years)		5 years
Management and Accounting Services | Senior housing | Brookdale JV | Minimum
Income Statements:
Management agreement term (in years)		10 years
Management and Accounting Services | Senior housing | Brookdale JV | Maximum
Income Statements:
Management agreement term (in years)		15 years
Assets | Tenants and Operators | Senior housing | Brookdale JV
Concentration of risk
Concentration risk (as a percent)		27.00%		28.00%
Assets | Tenants and Operators | Senior housing | HCRMC
Concentration of risk
Concentration risk (as a percent)		12.00%		12.00%
Assets | Tenants and Operators | Post-acute/skilled | HCRMC
Concentration of risk
Concentration risk (as a percent)		77.00%		64.00%
Revenue | Tenants and Operators | Senior housing | Brookdale JV
Concentration of risk
Concentration risk (as a percent)		21.00%	25.00%
Revenue | Tenants and Operators | Senior housing | HCRMC
Concentration of risk
Concentration risk (as a percent)		6.00%	8.00%
Revenue | Tenants and Operators | Post-acute/skilled | HCRMC
Concentration of risk
Concentration risk (as a percent)		78.00%	80.00%

[1] HCP, Inc.’s consolidated total assets and total liabilities at March 31, 2016 and December 31, 2015 include certain assets of variable interest entities (“VIEs”) that can only be used to settle the liabilities of the related VIE. The VIE creditors do not have recourse to HCP, Inc. Total assets at March 31, 2016 include VIE assets as follows: buildings and improvements $3.4 billion; development costs $60 million; land $327 million; accumulated depreciation and amortization $567 million; investments in unconsolidated joint ventures $14 million; accounts receivable $18 million; cash $60 million; restricted cash $23 million; intangible assets, net $197 million; and other assets, net $66 million. Total assets at December 31, 2015 include VIE assets as follows: buildings and improvements $3.4 billion; development costs $54 million; land $327 million; accumulated depreciation and amortization $537 million; investments in unconsolidated joint ventures $14 million; accounts receivable $19 million; cash $61 million; restricted cash $21 million; intangible assets, net $204 million; and other assets, net $63 million. Total liabilities at March 31, 2016 include VIE liabilities as follows: mortgage debt $573 million; intangible liabilities, net $10 million; accounts payable and accrued liabilities of $107 million and deferred revenue of $23 million from VIEs. Total liabilities at December 31, 2015 include VIE liabilities as follows: mortgage debt $589 million; intangible liabilities, net $10 million; accounts payable and accrued liabilities of $107 million and deferred revenue of $19 million. See Note 16 to the Consolidated Financial Statements for additional information.