Supplemental Guarantors Consolidating Condensed Financial Information - Statement of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Condensed Financial Statements, Captions
Net income (loss)	$ (1,903)	$ (13,379)
Foreign currency translation adjustments	(3,196)	822
Comprehensive income (loss)	(5,099)	(12,557)
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions
Net income (loss)	(4,123)	7,520
Foreign currency translation adjustments	24	111
Comprehensive income (loss)	(4,099)	7,631
Parent [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
Net income (loss)	(1,903)	(13,379)
Foreign currency translation adjustments	0	0
Comprehensive income (loss)	(1,903)	(13,379)
Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
Net income (loss)	4,438	(7,395)
Foreign currency translation adjustments	0	0
Comprehensive income (loss)	4,438	(7,395)
Non-Guarantor Subsidiaries [Member] \| Reportable Legal Entities [Member]
Condensed Financial Statements, Captions
Net income (loss)	(315)	(125)
Foreign currency translation adjustments	(3,220)	711
Comprehensive income (loss)	$ (3,535)	$ 586

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 5
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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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