Pro Forma Results of Combined Company Operations (Detail) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Business Acquisition Pro Forma Information [Abstract]
Total Revenues	$ 205,830	$ 199,864	$ 401,276	$ 411,546
Net income	$ 4,430	$ 6,009	$ 2,648	$ 6,010
Income per share
Basic	$ 0.11	$ 0.15	$ 0.07	$ 0.15
Diluted	$ 0.11	$ 0.15	$ 0.07	$ 0.15

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=25497992&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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