CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (90,433)	$ 10,617	$ 98,548
Other comprehensive income (loss), net of tax
Unrealized gain (loss) on available-for-sale marketable securities	249	(17)	(63)
Foreign currency translation adjustments	(155)	(6,600)	9,559
Total other comprehensive income (loss), net of tax	94	(6,617)	9,496
Comprehensive (loss) income	$ (90,339)	$ 4,000	$ 108,044

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 after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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