Earnings Per Common Share - Schedule of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator
Net income (loss)	$ 64,990	$ 43,237
Noncontrolling interests' share in earnings	(3,520)	(3,005)
Net income (loss) attributable to HCP, Inc.	61,470	40,232
Less: Participating securities' share in earnings	(441)	(391)
Net income (loss) applicable to common shares	$ 61,029	$ 39,841
Denominator
Basic weighted average shares outstanding (in shares)	477,766	469,557
Dilutive potential common shares - equity awards (in shares)	272	138
Dilutive potential common shares - forward equity agreements (in shares)	1,093	0
Diluted weighted average common shares (in shares)	479,131	469,695
Basic earnings per common share
Earnings per common share, basic (in dollars per share)	$ 0.13	$ 0.08
Earnings per common share, diluted (in dollars per share)	$ 0.13	$ 0.08