CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Real estate properties, at cost:
Land	$ 1,416,807	$ 1,360,773
Buildings, improvements and equipment	5,084,160	4,879,908
Total real estate properties, gross	6,500,967	6,240,681
Accumulated depreciation	(1,446,968)	(1,367,868)
Total real estate properties, net	5,053,999	4,872,813
Property held for sale	18,440	18,440
Cash and cash equivalents	24,771	8,303
Restricted cash (FF&E reserve escrow)	47,467	50,196
Other assets, net	218,302	183,821
Total assets	5,362,979	5,133,573
LIABILITIES AND SHAREHOLDERS' EQUITY
Unsecured revolving credit facility		149,000
Unsecured term loan	400,000
Senior notes, net of discounts	1,787,834	1,887,891
Convertible senior notes, net of discount	8,478	78,823
Security deposits	91,681	106,422
Accounts payable and other liabilities	118,798	103,668
Due to related persons	4,271	3,713
Dividends payable	8,006	4,754
Total liabilities	2,419,068	2,334,271
Commitments and contingencies
Preferred shares of beneficial interest, no par value, 100,000,000 shares authorized:
Common shares of beneficial interest, $.01 par value; 200,000,000 shares authorized; 123,563,407 and 123,521,535 shares issued and outstanding, respectively	1,236	1,235
Additional paid in capital	3,464,667	3,463,534
Cumulative net income	2,310,643	2,232,953
Cumulative other comprehensive income	3,684	1,605
Cumulative preferred distributions	(235,191)	(213,281)
Cumulative common distributions	(3,188,068)	(3,076,883)
Total shareholders' equity	2,943,911	2,799,302
Total liabilities and shareholders' equity	5,362,979	5,133,573
Series B
Preferred shares of beneficial interest, no par value, 100,000,000 shares authorized:
Preferred shares		83,306
Series C
Preferred shares of beneficial interest, no par value, 100,000,000 shares authorized:
Preferred shares	306,833	306,833
Series D
Preferred shares of beneficial interest, no par value, 100,000,000 shares authorized:
Preferred shares	$ 280,107