Pro Forma of Financial Information Purport to Represent Result of Operations (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Real Estate Properties Base Purchase Price [Abstract]
Pro forma total revenue (unaudited)	$ 16,735	$ 15,033	$ 50,653	$ 45,098
Pro forma net income (loss) allocable to common shares (unaudited)	$ 4,702	$ 2,961	$ 13,237	$ 8,882
Earnings (loss) per share attributable to common shareholders:
Basic-pro forma (unaudited)	$ 0.14	$ 0.12	$ 0.41	$ 0.47
Diluted-pro forma (unaudited)	$ 0.13	$ 0.12	$ 0.39	$ 0.47

Business Acquisition, Pro Forma, Earnings Per Share [Abstract]

No definition available.

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- Definition

Real estate properties base purchase price.

+ References

No definition available.

+ Details

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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

+ Details

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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

+ Details

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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

+ Details

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