Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (82,372)	$ (95,357)	$ (91,863)
Other comprehensive (loss) income:
Unrealized gain (loss) on marketable securities, net of tax of $0	239	121	(155)
Foreign currency translation adjustments, net of tax of $0	(765)	(1,074)	3,732
Comprehensive loss	$ (82,898)	$ (96,310)	$ (88,286)

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

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