CONCENTRATION OF CREDIT RISK (Details 2) (USD $) In Millions, unless otherwise specified	1 Months Ended	3 Months Ended	12 Months Ended	3 Months Ended				12 Months Ended	3 Months Ended
	Apr. 30, 2012 KINDRED asset group	Mar. 31, 2012 KINDRED property asset group renewal	Apr. 30, 2013 KINDRED	Mar. 31, 2012 KINDRED Minimum	Mar. 31, 2012 KINDRED Maximum	Mar. 31, 2012 ATRIA	Mar. 31, 2012 SUNRISE	Dec. 31, 2011 SUNRISE Minimum	Mar. 31, 2012 SUNRISE 2012 Plan	Mar. 31, 2012 SUNRISE 2012 Plan Minimum	Mar. 31, 2012 SUNRISE 2012 Plan Maximum	Mar. 31, 2012 Seniors housing communities property
Real estate properties
Properties		197
Term of lease (in years)				10 years	15 years
Number of renewals during lease term		3
Term of lease renewal (in years)		5 years
Number of groups set to expire		10
Number of triple-net lease properties set to expire under terms of lease		89
Number of renewal groups	3
Number of Renewal Assets	25
Current aggregate annual base rent for the Renewal Assets	$ 46
Number of Remaining 2013 Renewal Groups		7
Number of Remaining 2013 Marketed Assets		64
Amount of annual base rent of triple-net lease properties set to expire under terms of lease			$ 77
Minimum number of properties in each group		6
Minimum number of hospitals in each group		1
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 properties excluding Renewal Assets, set to expire under terms of lease		108
Number of sequential five-year renewal options		2
Number of seniors housing communities under long-term management agreements												198
Term of agreement (in years)						10 years	30 years
Successive automatic renewal period (in years)						10 years
Percentage of revenues charged for managing real estate properties								3.75%	6.00%	5.00%	7.00%