UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Foreign currency translation adjustments, tax	$ 0	$ 0
Foreign currency losses on intercompany loan of a long-term investment nature, tax	0
Unrealized holding gains on available-for-sale debt securities, tax	$ 0	$ 0

Amount of tax expense (benefit), 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, attributable to parent entity.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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