v2.4.0.6
Acquisitions of Real Estate Property (Details 2) (USD $)
 12 Months Ended
Dec. 31, 2012
Aug. 31, 2012
Sep. 30, 2011
May 12, 2011
Sep. 30, 2011
MOB Operations
Sep. 30, 2011
Operating Assets
Dec. 31, 2011
NHP
Sep. 30, 2011
NHP
Business acquisition                
Conversion ratio of acquired entity common stock to parent common stock (in shares)             0.7866  
Amount paid for closing of revolving credit facility             $ 105,000,000  
Number of properties acquired             643  
Fair values of the assets acquired and liabilities assumed at the date of acquisition                
Land and improvements 194,812,000             701,154,000
Buildings and improvements 1,721,060,000             6,147,737,000
Acquired lease intangibles 202,799,000             493,125,000
Investment in unconsolidated entities               93,553,000
Other assets 45,876,000             815,968,000
Total assets acquired 2,190,144,000             8,251,537,000
Notes payable and other debt 412,825,000             1,882,752,000
Other liabilities 127,682,000             720,420,000
Total liabilities assumed 540,507,000             2,603,172,000
Redeemable OP unitholder interests assumed               100,888,000
Noncontrolling interest assumed (including redeemable interests) 37,698,000             76,658,000
Net assets acquired 1,611,939,000             5,470,819,000
Cash acquired 24,871,000             29,205,000
Equity issued               5,365,819,000
Total cash used 1,587,068,000 350,000,000           75,795,000
Goodwill included in other assets     $ 399,000,000 $ 80,500,000 $ 338,500,000 $ 60,500,000