Consolidated Statements Equity (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock [Member] Class E [Member]	Common Stock [Member] Class A [Member]	Common Stock [Member] Class M [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Distributions to Stockholders [Member]	Accumulated Deficit [Member]	Noncontrolling Interest [Member]
Beginning balance at Dec. 31, 2009	$ 289,166	$ 41	$ 0	$ 0	$ 453,244	$ (39)	$ (78,361)	$ (98,299)	$ 12,580
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, Issued		23,928,784	0	0
Net income (loss)	(36,730)							(35,640)	(1,090)
Other comprehensive income (loss)	501					501
Cash contributed from noncontrolling interests	529								529
Cash distributed to noncontrolling interests	(757)								(757)
Ending balance at Dec. 31, 2010	252,709	41	0	0	453,244	462	(78,361)	(133,939)	11,262
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, Issued		23,995,352	0	0
Issuance of common stock (in shares)		66,568	0	0
Issuance of common stock	617	0	0	0	617	0	0	0	0
Net income (loss)	(19,638)							(19,388)	(250)
Other comprehensive income (loss)	(140)					(140)
Cash contributed from noncontrolling interests	756								756
Cash distributed to noncontrolling interests	(950)								(950)
Dividends, Common Stock	2,275						2,275
Ending balance at Dec. 31, 2011	231,079	41	0	0	453,861	322	(80,636)	(153,327)	10,818
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares, Issued		26,444,843	3,612,169	104,282
Issuance of common stock (in shares)		5,202,625	3,612,169	100,282
Issuance of common stock	88,846	9	36	1	88,800	0	0	0	0
Repurchase of shares (in shares)	2,748,659	(2,753,134)
Repurchase of shares	(26,885)	(5)			(26,880)
Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs	(3,219)				(3,219)
Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures				4,000
Stock based compensation	40				40
Stock Issued During Period, Value, Stock Dividend		219			(219)
Net income (loss)	37,335							37,476	(141)
Other comprehensive income (loss)	220					220
Cash contributed from noncontrolling interests	458								458
Cash distributed to noncontrolling interests	(734)								(734)
Dividends, Common Stock	10,055						10,055
Ending balance at Dec. 31, 2012	$ 317,085	$ 264	$ 36	$ 1	$ 512,383	$ 542	$ (90,691)	$ (115,851)	$ 10,401