Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (138,651)	$ (119,632)
Other comprehensive income (loss):
Net unrealized gain (loss) on available-for-sale investments	(5,121)	4,685
Net foreign currency translation gain (loss)	(751)	35
Other comprehensive income (loss)	(5,872)	4,720
Comprehensive loss	$ (144,523)	$ (114,912)

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 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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