Acquisitions Acquisitions - Unaudited Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016
Business Combinations [Abstract]
Revenue	$ 171,252	$ 152,787
Net income / (loss)	$ 21,445	$ (7,243)
Net income / (loss) per diluted share (in dollars per share)	$ 0.44	$ (0.15)

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.

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=79982066&loc=d3e1392-128463

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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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