Investments in and Advances to Unconsolidated Joint Ventures - Combined Financial Information for the unconsolidated joint ventures(Details) $ in Thousands			3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 25, 2015 USD ($) item	Mar. 30, 2015 USD ($) property	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($) property	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($) property	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Summarized combined financial information for equity method investments:
Real estate, net			$ 4,434,643		$ 4,434,643		$ 4,470,249
Goodwill and other assets, net			4,945,250		4,945,250		4,935,343
Assets held for sale			67,817		67,817		94,866
Total assets			9,447,710		9,447,710		9,500,458
Capital lease obligations and mortgage debt			6,419,016		6,419,016		6,575,531
Accounts payable			1,314,659		1,314,659		1,111,350
Liabilities and mortgage debt held for sale			1,593		1,593		6,318
Other partners' capital			1,078,758		1,078,758		1,163,501
HCP's capital			633,684		633,684		643,758
Total liabilities and partners' capital			9,447,710		9,447,710		9,500,458
Combined basis difference			42,000		42,000
Total revenues			1,057,213	$ 1,106,667	3,210,868	$ 3,375,747
Income (loss) from discontinued operations			904	(1,794)	3,476	(15,696)
Net (loss) income			(43,248)	(65,819)	(81,214)	(77,529)
HCP's share of earnings			(2,053)	8,314	(4,028)	33,916
Fees earned by HCP			76	454	248	1,372
Distributions received by HCP			$ 10,754	16,186	$ 20,377	20,673
Subsequent Events
Other than temporary impairment charge				27,234		27,234
MBK Development JV
Subsequent Events
Payment to acquire land	$ 3,000
Number of units to be built | item	74
HCRMC
Subsequent Events
Other than temporary impairment charge						27,000	$ 19,000	$ 36,000
HCRMC | Post-acute/skilled nursing
Summarized combined financial information for equity method investments:
Recharacterized DFL income to equity income				$ 14,000		$ 44,000
MBK JV
Subsequent Events
Debt related to retirement communities or properties contributed		$ 78,000
MBK JV | Senior housing
Subsequent Events
Investment ownership percentage		50.00%
Cash contributed		$ 27,000
Number of retirement communities | property				3		3
MBK JV | Senior housing | MBK
Subsequent Events
Number of retirement communities contributed to joint venture | property		3
Fair value of retirement communities or properties contributed		$ 126,000