Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Real estate investments:
Land	$ 182,313	$ 183,651
Building and improvements	2,102,743	2,044,113
Lease intangibles	360,937	352,884
Property held for sale, net	21,138	0
Real estate investments, gross	2,667,131	2,580,648
Accumulated depreciation and amortization	(392,102)	(349,118)
Real estate investments, net	2,275,029	2,231,530
Real estate notes receivable	20,000	20,000
Cash and cash equivalents	120,871	15,956
Restricted cash and escrow deposits	18,268	17,623
Receivables and other assets, net	97,289	84,970
Other intangibles, net	42,237	44,011
Non-real estate assets of property held for sale, net	1,059	0
Total assets	2,574,753	2,414,090
Liabilities:
Debt, net	1,114,204	1,037,359
Accounts payable and accrued liabilities	71,661	63,443
Derivative financial instruments - interest rate swaps	2,065	9,370
Security deposits, prepaid rent and other liabilities	28,966	24,450
Intangible liabilities, net	10,823	11,309
Total liabilities	1,227,719	1,145,931
Commitments and contingencies
Redeemable noncontrolling interest of limited partners	3,423	3,564
Equity:
Preferred stock, $0.01 par value; 200,000,000 shares authorized; none issued and outstanding	0	0
Additional paid-in capital	2,011,333	1,885,836
Cumulative dividends in excess of earnings	(683,076)	(633,717)
Total stockholders’ equity	1,330,518	1,254,266
Noncontrolling interest	13,093	10,329
Total equity	1,343,611	1,264,595
Total liabilities and equity	2,574,753	2,414,090
Class A
Equity:
Common stock, $0.01 par value	1,688	1,001
Class B
Equity:
Common stock, $0.01 par value	$ 573	$ 1,146