CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (7,977)	$ (28,515)
Other comprehensive (loss) income:
Foreign currency translation adjustments	695	123
Change in fair value of derivatives qualifying as cash flow hedges	132	(633)
Other comprehensive income (loss) before income tax (expense) benefit	827	(510)
Income tax (expense) benefit related to items in other comprehensive (loss) income	(35)	314
Total other comprehensive income (loss)	792	(196)
Comprehensive loss	(7,185)	(28,711)
Comprehensive loss attributable to non-controlling interests	424	790
Comprehensive (loss) income, net	$ (6,761)	$ (27,921)

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.

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Amount before tax, after reclassification adjustments of other comprehensive income (loss).

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Amount before tax, after 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 and reclassification adjustments of other comprehensive income (loss).

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