Potential Acquisitions - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Mar. 31, 2014 sqft Store
Raleigh/Myrtle Beach Portfolio
Business Acquisition [Line Items]
Number of wholly-owned self storage facilities	5
Business acquisition purchase price	$ 22.1
Loans assumed as purchase consideration	$ 12.8
Number of operation units	2,500
Total rental area	355,000
Raleigh, North Carolina
Business Acquisition [Line Items]
Number of wholly-owned self storage facilities	3
Myrtle Beach, South Carolina
Business Acquisition [Line Items]
Number of wholly-owned self storage facilities	2

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

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