Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net (loss) earnings	$ (8,893)	$ 9,946	$ (15,572)	$ 35,007
Foreign currency translation adjustments	1,181	(1,377)	6,736	1,073
Total other comprehensive (loss) income	1,181	(1,377)	6,736	1,073
Comprehensive (loss) income	$ (7,712)	$ 8,569	$ (8,836)	$ 36,080

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
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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.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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