Acquisition (Selected Financial Information) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2015
Enterprise Offshore Acquisition
SelectedFinancialInformation [Line Items]
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	$ 24,471	$ 24,471
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	44,713	44,713
American Phoenix Acquisition [Member]
SelectedFinancialInformation [Line Items]
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual	1,381	4,052
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	$ 5,637	$ 16,859

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting 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)(1)

-URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Details

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