Selected Quarterly Financial Data (Unaudited) - Results of Operations for Properties Sold or to be Sole (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Selected Quarterly Financial Data (Unaudited)
Total revenues	$ 668,036	$ 657,953	$ 607,532	$ 610,791	$ 603,528	$ 596,638	$ 536,121	$ 529,992	$ 2,544,312	$ 2,266,279	$ 2,099,878
(Loss) income before income taxes and equity income from and impairments of investments in unconsolidated joint ventures	(601,744)	134,894	151,184	(251,181)	222,771	240,946	208,926	220,795	(566,847)	893,438	852,015
Total discontinued operations								29,746		29,746	74,373
Net (loss) income	(594,617)	117,954	167,748	(237,503)	199,630	251,059	222,279	263,623	(546,418)	936,591	985,006
Net (loss) income attributable to HCP, Inc.	$ (598,868)	$ 115,362	$ 164,885	$ (240,614)	$ 196,583	$ 247,654	$ 218,885	$ 259,111	$ (559,235)	$ 922,233	$ 970,837
Dividends paid per common share (in dollars per share)	$ 0.565	$ 0.565	$ 0.565	$ 0.565	$ 0.545	$ 0.545	$ 0.545	$ 0.545	$ 2.26	$ 2.18	$ 2.10
Basic earnings per common share (in dollars per share)	(1.290)	0.250	0.360	(0.520)	0.43	0.54	0.48	0.56	(1.21)	2.01	2.13
Diluted earnings per common share (in dollars per share	$ (1.290)	$ 0.250	$ 0.360	$ (0.520)	$ 0.43	$ 0.54	$ 0.48	$ 0.56	$ (1.21)	$ 2.00	$ 2.13