General - Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Revenues	$ 299,165	$ 350,953	$ 599,059	$ 668,068
Net income	$ 3,458	$ 9,665	$ (196)	$ 10,266
Earnings (loss) per share (in dollars per share)	$ 0.10	$ 0.26	$ (0.01)	$ 0.28

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=65885119&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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