Impairments (Details) (USD $)	12 Months Ended							12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2010 HCP Ventures II	Jan. 14, 2011 HCP Ventures II item	Oct. 31, 2010 HCP Ventures II item	Dec. 31, 2012 Land acre sqft	Dec. 31, 2011 Cirrus loan
Asset impairment
Area under expanded tenant relationship (in square feet)								396,000
Area of lease extension (in square feet)								281,000
Real estate lease term								10 years
Area of building to be developed (in square feet)								115,000
Land acquired (in acres)								19
Sales price of parcel								$ 19,000,000
Impairment related to parcel of land	7,878,000	15,400,000	59,793,000					7,900,000
Carrying value, land	1,850,397,000	1,722,948,000						27,000,000
Provision for losses (impairment)									15,400,000
Loans receivable, before Impairment	147,264,000	35,643,000							91,100,000
Loans receivable, after Impairment									75,700,000
Ownership interest (as a percent)							35.00%
Number of senior housing facilities						25	25
Impairment charges for direct financing lease				63,100,000	71,700,000
Carrying value, equity method investments before impairment					136,800,000
Fair value, equity method investments					$ 65,100,000