CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Real estate:
Buildings and improvements	$ 8,994,048	$ 8,933,278
Development costs and construction in progress	204,018	190,590
Land	1,734,469	1,729,677
Accumulated depreciation and amortization	(1,614,148)	(1,472,272)
Net real estate	9,318,387	9,381,273
Net investment in direct financing leases	6,804,929	6,727,777
Loans receivable, net	125,521	110,253
Investments in and advances to unconsolidated joint ventures	219,877	224,052
Accounts receivable, net of allowance of $1,696 and $1,341, respectively	25,974	26,681
Cash and cash equivalents	169,636	33,506
Restricted cash	42,782	41,553
Intangible assets, net	347,670	373,763
Real estate held for sale, net		4,159
Other assets, net	734,992	485,458
Total assets	17,789,768	17,408,475
LIABILITIES AND EQUITY
Bank line of credit	215,015	454,000
Senior unsecured notes	5,615,979	5,416,063
Mortgage debt	1,726,944	1,764,571
Other debt	84,060	87,985
Intangible liabilities, net	114,939	124,142
Accounts payable and accrued liabilities	273,344	275,478
Deferred revenue	68,548	65,614
Total liabilities	8,098,829	8,187,853
Commitments and contingencies
Preferred stock, $1.00 par value: aggregate liquidation preference of $295.5 million as of December 31, 2011		285,173
Common stock, $1.00 par value: 750,000,000 shares authorized; 429,401,611 and 408,629,444 shares issued and outstanding, respectively	429,402	408,629
Additional paid-in capital	10,159,580	9,383,536
Cumulative dividends in excess of earnings	(1,062,049)	(1,024,274)
Accumulated other comprehensive loss	(19,703)	(19,582)
Total stockholders' equity	9,507,230	9,033,482
Joint venture partners	15,855	16,971
Non-managing member unitholders	167,854	170,169
Total noncontrolling interests	183,709	187,140
Total equity	9,690,939	9,220,622
Total liabilities and equity	$ 17,789,768	$ 17,408,475