OTHER NONCONTROLLING INTERESTS (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended		12 Months Ended
	Oct. 31, 2010 JointVenture	Jun. 30, 2010 Property	Dec. 31, 2011 Property
Other noncontrolling interests
Other Noncontrolling Interests
Number of consolidated self-storage properties			3
Number of consolidated self-storage properties under development			2
Number of consolidated self-storage properties under lease-up stage			1
Cash paid for acquiring equity interests in joint ventures	$ 500
Number of real estate joint ventures in which entity acquired an equity interest during the period	3
Number of self-storage properties in which minority partners' membership interests is acquired		2
Payment to acquire minority partners' interests in consolidated self-storage properties		50
Loss on reassessment of the property			$ 800
Noncontrolling Interest [Member] | Minimum
Other Noncontrolling Interests
Ownership interests of third party owners (as a percent)			10.00%
Noncontrolling Interest [Member] | Maximum
Other Noncontrolling Interests
Ownership interests of third party owners (as a percent)			27.60%