Organization - Additional Information (Detail) (USD $)	3 Months Ended		12 Months Ended	1 Months Ended	6 Months Ended			3 Months Ended
	Mar. 31, 2014 States Property	Mar. 31, 2013	Dec. 31, 2013	Feb. 28, 2013 West Deptford JV LLC [Member]	Jun. 30, 2011 West Deptford JV LLC [Member]	Mar. 31, 2014 Sovran HHF Storage Holdings LLC [Member] Property	Mar. 31, 2014 Sovran HHF Storage Holdings II LLC [Member] Property	Mar. 31, 2014 Texas and Florida [Member] Revenue [Member]
Organization [Line Items]
Number of self-storage properties owned and managed	485
Number of states in which self-storage properties owned and managed	25
Number of properties owned and managed under twenty-percent stake joint venture						25
Percentage ownership in unconsolidated joint venture						20.00%	15.00%
Number of properties managed with no ownership	22
Number of properties owned and managed under fifteen-percent stake joint venture							30
Concentration risk, percentage								40.00%
Number of properties leased	4
Percentage of ownership interest of the subsidiary and its limited partnership which controls the operations of the Operating Partnership	99.40%
Percentage ownership in consolidated joint venture					20.00%
Payments to acquire businesses and interest in affiliates					$ 4,200,000
Mortgage note acquired					2,800,000
Interest rate for mortgage notes acquired					8.00%
Payments to acquire preferred interest in affiliates					1,400,000
Preferred interest in investment					8.00%
Membership Interest Purchase Agreement, common and preferred interests				1,400,000
Joint venture partner repaid				2,800,000
Gain on sale of real estate		$ 421,000		$ 400,000
Units of redeemable noncontrolling interest in operating partnership	198,913		198,913
Noncontrolling limited partnership unit redemption value	One common share or cash