Noncontrolling Interests (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2010
Noncontrolling Interest [Line Items]
Net Income (Loss) Available to Common Stockholders, Basic	$ 4,261,000	$ 145,721,000	$ 3,062,000	$ 226,569,000
Change in equity from net loss income attributable to common stockholders and conversion of operating partnership units to companys common stock	4,323,000	145,867,000	4,773,000	226,715,000
Redeemable noncontrolling interests in the Operating Partnership
Mark to market adjustment to redeemable noncontrolling interests in the OP			20,402,000
Adjustment for conversion of non-controlling interest of unitholders in Operating Partnership	(62,000)	(146,000)	(1,711,000)	(146,000)	(1,711,000)
Net (income)/loss attributable to redeemable non-controlling interests in OP	159,000	5,911,000	114,000	9,331,000
Distributions to redeemable noncontrolling interests in the OP			(4,721,000)
Allocation of other comprehensive (loss)/income	64,000	29,000	151,000	(38,000)
Redeemable non-controlling interests in operating partnership	237,653,000	223,418,000	237,653,000	223,418,000
Net income attributable to non-controlling interests	$ 3,000	$ 43,000	$ 7,000	$ 95,000