Consolidated Statements of Equity (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Class B [Member]	Common Stock [Member]	Common Stock [Member]	Series B Cumulative Redeemable Preferred Stock [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member] Common Class B [Member]	Additional Paid-in Capital [Member] Common Stock [Member]	Accumulated Deficit [Member]	Accumulated Other Comprehensive (Deficit) Income [Member]	Non-controlling Interests- Common units in the Operating Partnership [Member]	Non-controlling Interests- Members in Consolidated Entities [Member]	Non-controlling Interests- Series A Cumulative Redeemable Preferred Units [Member]
Beginning balance at Dec. 31, 2011	$ 688,669			$ 338	$ 87,500	$ 552,043			$ (13,685)	$ (883)	$ 63,356		$ 12,475
Beginning balance (in shares) at Dec. 31, 2011				33,840,854
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from sale of stock	57,500				57,500
Common stock issuance transaction costs		(1,865)					(1,865)
Issuance of unrestricted stock (in shares)				1,766
Issuance of unrestricted stock		0
Declared Dividend	(7,595)				(3,036)	(4,252)					(307)		(195)
Amortization of stock based compensation	1,167					1,167
Net income (loss)	273				3,036				(2,560)		(203)		195
Cash Flow Hedge Adjustment	(91)									(85)	(6)
Exchange of Non controlling Interests, Common Units in the Operating Partnership for Common Stock, Shares				155,878
Exchange of Non controlling Interests, Common Units in the Operating Partnership for Common Stock	0			2		3,780					(3,782)
Ending balance at Mar. 31, 2012	738,058			340	145,000	550,873			(16,245)	(968)	59,058		12,475
Ending balance (in shares) at Mar. 31, 2012				33,998,498
Beginning balance at Dec. 31, 2012	897,222			475	145,000	726,605			(30,580)	(1,287)	55,549	1,460	12,475
Beginning balance (in shares) at Dec. 31, 2012	47,493,732			47,496,732
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Proceeds from sale of stock (in shares)				9,200,000
Proceeds from sale of stock	189,888			92		189,796
Common stock issuance transaction costs			(305)					(305)
Issuance of unrestricted stock (in shares)				1,424
Issuance of unrestricted stock	0
Declared Dividend	(10,421)				(3,036)	(7,087)					(298)		(195)
Amortization of stock based compensation	1,783					1,783
Net income (loss)	122				3,036				(2,793)		(131)	10	195
Cash Flow Hedge Adjustment	17									16	1
Exchange of Non controlling Interests, Common Units in the Operating Partnership for Common Stock						0
Ending balance at Mar. 31, 2013	$ 1,078,306			$ 567	$ 145,000	$ 910,792			$ (33,373)	$ (1,271)	$ 55,121	$ 1,470	$ 12,475
Ending balance (in shares) at Mar. 31, 2013	56,698,156			56,698,156