Concentration of Credit Risk (Details 2) (USD $)	1 Months Ended	12 Months Ended
	Nov. 30, 2011 bundle asset	Apr. 30, 2012	Dec. 31, 2011 notice property lease asset bundle renewal
Future contracted minimum rentals leases
2012			$ 1,019,968,000
2013			925,558,000
2014			864,252,000
2015			738,226,000
2016			640,745,000
Thereafter			3,409,149,000
Total			7,597,898,000
Brookdale Senior Living
Future contracted minimum rentals leases
2012			161,203,000
2013			160,018,000
2014			149,316,000
2015			138,514,000
2016			136,846,000
Thereafter			439,387,000
Total			1,185,284,000
KINDRED
Future contracted minimum rentals leases
2012			260,530,000
2013			181,126,000
2014			142,730,000
2015			48,785,000
2016			1,009,000
Total			634,180,000
Number of renewals during lease term			3
Term of lease renewal (in years)			5 years
Number of bundles set to expire			10
Number of triple-net lease properties set to expire under terms of lease			89
Minimum number of renewal notices needed on bundles set to expire in following year in order to extend lease term			1
Minimum number of properties in each bundle			6
Minimum number of hospitals in each bundle			1
Amount of annual base rent of triple-net lease properties set to expire under terms of lease		99,000,000
Minimum period to reposition triple-net lease properties with new operators if a renewal notice on is not received (in years)			1 year
Number of Early Renewal Assets	16
Number of Early Renewal Bundles	2
Current aggregate annual base rent for the Early Renewal Assets	23,000,000
Number of Remaining 2013 Renewal Assets			73
Number of Remaining 2013 Renewal Bundles			8
Number of remaining reset bundles	4
Number of Remaining Reset Assets	37
Current aggregate annual base rent for the Remaining Reset Assets	43,000,000
Number of sequential renewal options			2
Number of properties excluding Renewal Assets, set to expire under terms of lease			108
Number of leases			197
KINDRED | Minimum
Future contracted minimum rentals leases
Term of lease (in years)			10 years
KINDRED | Maximum
Future contracted minimum rentals leases
Term of lease (in years)			15 years
SUNRISE
Future contracted minimum rentals leases
Term of agreement (in years)			30 years
SUNRISE | Minimum
Future contracted minimum rentals leases
Percentage of revenues charged for managing real estate properties			3.75%
SUNRISE | 2012 Plan
Future contracted minimum rentals leases
Percentage of revenues charged for managing real estate properties			6.00%
SUNRISE | 2012 Plan | Minimum
Future contracted minimum rentals leases
Percentage of revenues charged for managing real estate properties			5.00%
SUNRISE | 2012 Plan | Maximum
Future contracted minimum rentals leases
Percentage of revenues charged for managing real estate properties			7.00%
ATRIA
Future contracted minimum rentals leases
Term of agreement (in years)			10 years
Successive automatic renewal period (in years)			10 years
Other
Future contracted minimum rentals leases
2012			598,235,000
2013			584,414,000
2014			572,206,000
2015			550,927,000
2016			502,890,000
Thereafter			2,969,762,000
Total			$ 5,778,434,000
Long-term accute care hospital assets
Future contracted minimum rentals leases
Number of Early Renewal Assets	3
Seniors housing communities
Future contracted minimum rentals leases
Number of seniors housing communities under long-term management agreements			197