Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (25,800)	$ (35,202)
Other comprehensive (loss) income, net of tax:
Change in unrealized (losses) gains related to marketable securities	(172)	370
Foreign currency translation adjustments	5	0
Total other comprehensive (loss) income	(167)	370
Comprehensive loss	$ (25,967)	$ (34,832)

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 and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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