Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (58,014)	$ (103,130)
Other comprehensive income, net of tax:
Foreign currency translation loss	(836)	(8)
Unrealized gain on investments	852	350
Total other comprehensive income, net of tax	16	342
Comprehensive loss	$ (57,998)	$ (102,788)

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, attributable to parent entity.

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