NONCONTROLLING INTEREST IN OPERATING PARTNERSHIP (Details) (Operating Partnership, USD $) In Thousands, except Share data, unless otherwise specified	1 Months Ended								12 Months Ended
	Apr. 30, 2011	Jan. 31, 2011	Aug. 31, 2010	Jul. 31, 2010	Dec. 31, 2009	Nov. 30, 2009	Jul. 31, 2009	Apr. 30, 2009	Dec. 31, 2011 D
Operating Partnership
Noncontrolling interest in operating partnership
Ownership interest held by entity (as a percent)									95.90%
Noncontrolling interest in operating partnership (as a percent)									4.10%
Common OP units outstanding									3,049,935
Number of days used as a denomination to determine the average closing price of common stock (in days)									10
Common OP units conversion basis									one-for-one basis
Ten day average closing stock price (in dollars per share)									$ 24.01
Consideration to be paid on redemption of common OP units									$ 73,229
Number of units redeemed during the period (in units)	143,641	150,000	180,270	90,135	72,643	217,930	232,099	114,928
Number of units redeemed for cash during the period (in units)	13,387
Cash consideration paid on redemption of common OP units	$ 271		$ 2,802	$ 1,314			$ 1,908