Quarterly Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Revenues	$ 187,322	$ 158,555	$ 149,407	$ 149,634	$ 186,439	$ 148,029	$ 146,906	$ 145,053	$ 644,918	$ 626,427	$ 637,458
Income (Loss) from Equity Method Investments	14,074	10,958	10,886	10,146	16,199	9,973	9,505	9,735	46,064	45,412	11,488
Net income (loss)	220,796	21,868	20,290	24,444	58,572	8,458	18,484	16,813	287,398	102,327	(79,161)
Net Income (Loss) Available to Common Stockholders, Basic	149,180	8,461	8,344	10,716	33,141	722	7,453	6,283	176,701	47,599	(69,706)
Income (Loss) from Continuing Operations, Per Basic Share	$ 0.53	$ 0.29	$ 0.23	$ 0.27	$ 0.66	$ 0.09	$ 0.20	$ 0.18	$ 1.32	$ 1.12	$ 0.90
Earnings Per Share, Basic	$ 2.58	$ 0.15	$ 0.15	$ 0.19	$ 0.61	$ 0.01	$ 0.14	$ 0.12	$ 3.11	$ 0.87	$ (1.31)
Income (Loss) from Continuing Operations, Per Diluted Share	$ 0.52	$ 0.28	$ 0.23	$ 0.26	$ 0.65	$ 0.09	$ 0.19	$ 0	$ 1.29	$ 1.11	$ 0.89
Earnings Per Share, Diluted	$ 2.50	$ 0.14	$ 0.15	$ 0.19	$ 0.60	$ 0.01	$ 0.14	$ 0.11	$ 3.03	$ 0.86	$ (1.30)
Gains (Losses) on Extinguishment of Debt									174,171
Regency Square Member
Gains (Losses) on Extinguishment of Debt									47,400
Pier Shops Member
Gains (Losses) on Extinguishment of Debt									$ 126,700