Acquisition - Pro Forma Results (Details) - Cogent Partners, LP - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Revenues	$ 73,342	$ 67,900	$ 145,700	$ 116,100
Income before taxes	15,800	12,300	29,800	12,500
Net income allocated to common stockholders	$ 9,400	$ 7,900	$ 18,200	$ 8,100
Diluted earnings per share	$ 0.30	$ 0.26	$ 0.59	$ 0.26

Business Acquisition, Pro Forma Net Income (Loss), Before Tax

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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

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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+ References

No definition available.

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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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