Investment in Storage Facilities - Pro Forma Information Based on Combined Historical Financial Statements on Properties Acquired (Detail) - Jun. 30, 2014 - USD ($) $ / shares in Units, $ in Thousands	Total	Total
Investments Schedule [Abstract]
Total revenues	$ 84,288	$ 163,990
Net income attributable to common shareholders	$ 22,836	$ 42,191
Basic	$ 0.68	$ 1.25
Diluted	$ 0.67	$ 1.25

No definition available.

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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- Definition

The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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