Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Investment properties:
Land	$ 1,255,881	$ 1,334,363
Building and other improvements	4,896,652	5,057,252
Developments in progress	49,433	49,940
Gross investment properties	6,201,966	6,441,555
Less accumulated depreciation	(1,284,426)	(1,180,767)
Net investment properties	4,917,540	5,260,788
Cash and cash equivalents	107,423	136,009
Investment in marketable securities, net	9,347	30,385
Investment in unconsolidated joint ventures	53,617	81,168
Accounts and notes receivable (net of allowances of $6,564 and $8,231, respectively)	79,709	94,922
Acquired lease intangibles, net	139,442	174,404
Investment properties held for sale	8,633	0
Other assets, net	166,877	164,218
Total assets	5,482,588	5,941,894
Liabilities:
Mortgages and notes payable	2,396,899	2,926,218
Credit facility	535,000	555,000
Accounts payable and accrued expenses	87,725	83,012
Distributions payable	38,200	31,448
Acquired below market lease intangibles, net	77,103	81,321
Other financings	0	8,477
Co-venture obligation	0	52,431
Liabilities associated with investment properties held for sale	228	0
Other liabilities	68,858	66,944
Total liabilities	3,204,013	3,804,851
Redeemable noncontrolling interests	0	525
Commitments and contingencies (Note 16)
Equity:
Preferred stock, $0.001 par value, 10,000 shares authorized, none issued or outstanding	0	0
Additional paid-in capital	4,705,024	4,427,977
Accumulated distributions in excess of earnings	(2,436,010)	(2,312,877)
Accumulated other comprehensive income	7,836	19,730
Total shareholders' equity	2,277,081	2,135,024
Noncontrolling interests	1,494	1,494
Total equity	2,278,575	2,136,518
Total liabilities and equity	5,482,588	5,941,894
Class A common stock
Equity:
Common stock	85	48
Class B-1 common stock
Equity:
Common stock	48	48
Class B-2 common stock
Equity:
Common stock	49	49
Class B-3 common stock
Equity:
Common stock	$ 49	$ 49