Consolidated Unaudited Pro Forma Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Business Combinations [Abstract]
Pro forma total revenue (unaudited)	$ 85,356	$ 80,330	$ 173,700	$ 156,174
Pro forma net income (loss) allocable to common shares (unaudited)	$ (7,546)	$ 18,930	$ (25,355)	$ 11,807
Basic-as pro forma (unaudited)	$ (0.08)	$ 0.23	$ (0.28)	$ 0.14
Diluted-as pro forma (unaudited)	$ (0.08)	$ 0.21	$ (0.28)	$ 0.14

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.

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=65885119&loc=d3e1392-128463

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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.

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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.

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

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No definition available.

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