SHAREHOLDERS' EQUITY AND NONCONTROLLING INTERESTS Noncontrolling Interest (Details) (USD $)	0 Months Ended	1 Months Ended	3 Months Ended								12 Months Ended					12 Months Ended			12 Months Ended								12 Months Ended
	Nov. 29, 2011	Feb. 27, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 LTIP Units [Member]	Dec. 31, 2011 LTIP Units [Member]	Dec. 31, 2011 Klaff [Member] Restricted Stock [Member]	Dec. 31, 2005 Klaff [Member] Restricted Stock [Member]	Dec. 31, 2012 Series A Preferred Stock [Member]	Dec. 31, 2012 Noncontrolling Interests	Dec. 31, 2011 Noncontrolling Interests	Dec. 31, 2010 Noncontrolling Interests	Dec. 31, 2012 Noncontrolling Interests Partially-Owned Affiliates [Member]	Dec. 31, 2012 Operating Partnership, as General Partner or Managing Member [Member]	Dec. 31, 2011 Operating Partnership, as General Partner or Managing Member [Member]	Dec. 31, 2012 Operating Partnership, as General Partner or Managing Member [Member] Series A Preferred Stock [Member]	Dec. 31, 2011 Operating Partnership, as General Partner or Managing Member [Member] Series A Preferred Stock [Member]	Dec. 31, 2012 Operating Partnership, as General Partner or Managing Member [Member] Noncontrolling Interests
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance						$ 385,195,000					$ 385,195,000											$ 375,203,000					$ 9,992,000
Distributions declared of $0.72 per Common OP Unit																						0					(1,098,000)
Distributions declared	$ 0.18	$ 0.21	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.18	$ 0.72	$ 0.72	$ 0.72
Net income for the period January 1 through December 31, 2012											50,230,000	2,160,000	20,610,000									49,702,000					528,000
Conversion of 334,445 OP Units to Common Shares by limited partners of the Operating Partnership																			(5,880,000)	(56,000)	(3,240,000)	0					(5,880,000)
Issuance of LTIP Unit awards to employees											2,577,000	2,441,000							2,577,000	2,441,000		0					2,577,000
Issuance of OP Units to acquire real estate											2,279,000	0	0						2,279,000			0					2,279,000
Other comprehensive income - unrealized loss on valuation of swap agreements											(3,519,000)	(5,611,000)	(2,683,000)						(1,704,000)	(2,150,000)	(354,000)	(1,632,000)					(72,000)
Reclassification of realized interest on swap agreements											(2,268,000)	(3,081,000)	(2,749,000)						(847,000)	(676,000)	(283,000)	827,000					20,000
Noncontrolling Interest contributions											172,228,000	117,945,000	33,556,000						172,228,000	117,945,000	33,556,000	172,228,000					0
Noncontrolling interest distributions and other reductions											(160,663,000)	(7,697,000)	(2,892,000)						(160,663,000)	(7,697,000)	(2,892,000)	(160,663,000)					0
Employee Long-term Incentive Plan Unit Awards											3,640,000	4,032,000	3,838,000						3,448,000	3,550,000	1,778,000	0					3,448,000
Balance			447,459,000				385,195,000				447,459,000	385,195,000										435,665,000					11,794,000
Series A Preferred OP Units																							284,097	279,748	188	188
Limited Partners' Capital Account, Value Per Unit																									1,000	1,000
Per Unit Conversion Amount, Series A Preferred OP Units																		22.50
Per Unit Conversion Annual Rate, Series A Preferred OP Units																		9.00%
Share-based Compensation, Units Outstanding														1,109,727	1,061,564
Units issued for interest in contractual rights (in shares)																	250,000
Units issued for interest in contractual rights, converted (in shares)																250,000
Limited Partners' Capital Account, Units Issued and Converted			334,445								334,445							1,392
Share-based Compensation, Units converted from Series A Preferred OP Units							185,600					185,600
Denominator for Series A Preferred OP Unit Conversion			$ 7.50								$ 7.50