CONDENSED CONSOLIDATED STATEMENT OF CHANGES IN EQUITY (Unaudited) (USD $) In Thousands	Total	Preferred Shares [Member]	Common Shares [Member]	Additional Paid-in-Capital [Member]	Accumulated Distributions in Excess of Net Income [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Non-controlling Interests [Member]
Balance at Dec. 31, 2009	$ 1,297,236	$ 327,867	$ 12	$ 1,750,979	$ (870,862)	$ 673	$ 88,567
Contributions from noncontrolling interests	883	0	0	0	0	0	883
Redemption of noncontrolling OP units for common shares	0	0	0	1,897	0	0	(1,897)
Transfer of Noncontrolling Interest	(1,957)	0	0	0	0	0	(1,957)
Issuance of Convertible Notes	13,134	0	0	13,134	0	0	0
Issuance of common shares and amortization of deferred compensation costs, net	80,949	0	1	80,948	0	0	0
Dividends/distributions	(66,457)	0	0	0	(58,840)	0	(7,617)
Comprehensive income (loss):
Net income (loss)	(51,687)	0	0	0	(44,534)	0	(7,153)
Other comprehensive income:
Change in unrealized gain on foreign currency translation, net	(740)	0	0	0	0	(740)	0
Change in unrealized gain (loss) on interest rate swap, net	(867)	0	0	0	0	(867)	0
Other comprehensive income (loss)	(1,607)
Comprehensive income (loss)	(53,294)
Balance at Sep. 30, 2010	1,270,494	327,867	13	1,846,958	(974,236)	(934)	70,826
Balance at Dec. 31, 2010	1,356,129	327,867	15	1,937,942	(985,562)	(106)	75,973
Redemption of noncontrolling OP units for common shares	0	0	0	1,876	0	0	(1,876)
Repurchase of preferred shares	(1,431)	(1,646)	0	0	215	0	0
Issuance of common shares and amortization of deferred compensation costs, net	99,437	0	1	99,436	0	0	0
Dividends/distributions	(75,695)	0	0	0	(71,789)	0	(3,906)
Comprehensive income (loss):
Net income (loss)	(103,794)	0	0	0	(92,611)	0	(11,183)
Other comprehensive income:
Change in unrealized gain (loss) on interest rate swap, net	1,342	0	0	0	0	1,342	0
Other comprehensive income (loss)	1,342
Comprehensive income (loss)	(102,452)
Balance at Sep. 30, 2011	$ 1,275,988	$ 326,221	$ 16	$ 2,039,254	$ (1,149,747)	$ 1,236	$ 59,008