Commitment and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014 Facility
Commitment And Contingencies [Line Items]
Payment for self-storage facilities under contract	$ 128.4
Number of self-storage facilities under contract to be purchased	18
Sovran HHF Storage Holdings LLC [Member]
Commitment And Contingencies [Line Items]
Payment for self-storage facilities under contract	47.1
Number of self-storage facilities under contract to be purchased	4
Cash contribution to subsidiaries	$ 9.4
Percentage ownership interest by parent	20.00%