CONDENSED CONSOLIDATED BALANCE SHEETS (unaudited) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Real estate properties:
Land	$ 456,614	$ 714,238
Buildings and improvements	3,834,855	5,014,205
Total real estate properties, at cost, gross	4,291,469	5,728,443
Accumulated depreciation	(913,303)	(1,030,445)
Total real estate properties, at cost, net	3,378,166	4,697,998
Properties held for sale	360,781	0
Acquired real estate leases, net	121,912	198,287
Cash and cash equivalents	1,286,902	364,516
Restricted cash	31,351	32,257
Rents receivable, net of allowance for doubtful accounts of $10,008 and $6,565, respectively	209,089	248,101
Other assets, net	159,845	220,480
Total assets	5,548,046	5,761,639
LIABILITIES AND SHAREHOLDERS’ EQUITY
Senior unsecured debt, net	1,460,131	1,598,416
Mortgage notes payable, net	513,561	609,249
Liabilities related to properties held for sale	20,336	0
Accounts payable and accrued expenses	128,590	162,204
Assumed real estate lease obligations, net	5,728	26,784
Rent collected in advance	21,860	31,359
Security deposits	10,610	14,044
Total liabilities	2,160,816	2,442,056
Common shares of beneficial interest, $0.01 par value:
Common shares of beneficial interest, $0.01 par value: 350,000,000 shares authorized; 129,760,214 and 129,607,279 shares issued and outstanding, respectively	1,298	1,296
Additional paid in capital	4,495,244	4,487,133
Cumulative net income	2,260,098	2,233,852
Cumulative other comprehensive loss	(5,963)	(53,216)
Cumulative common distributions	(3,111,868)	(3,111,868)
Cumulative preferred distributions	(636,233)	(622,271)
Total shareholders’ equity	3,387,230	3,319,583
Total liabilities and shareholders’ equity	5,548,046	5,761,639
Series D
Preferred shares of beneficial interest, $0.01 par value: 50,000,000 shares authorized;
Series D preferred shares; 6 1/2% cumulative convertible; 4,915,196 and 4,915,497 shares issued and outstanding, respectively, aggregate liquidation preference of $122,880 and $122,887, respectively	119,263	119,266
Series E
Preferred shares of beneficial interest, $0.01 par value: 50,000,000 shares authorized;
Series E preferred shares; 7 1/4% cumulative redeemable on or after May 15, 2016; 11,000,000 shares issued and outstanding, aggregate liquidation preference $275,000	$ 265,391	$ 265,391