CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (114,359)	$ (83,509)	$ (76,302)
Net change in unrealized gains (losses) on available-for-sale securities	(202)	10	(5)
Foreign currency translation adjustments	760	(120)	(42)
Other comprehensive income (loss)	558	(110)	(47)
Comprehensive loss	$ (113,801)	$ (83,619)	$ (76,349)

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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-Name Accounting Standards Codification
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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 appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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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 and reclassification adjustments of other comprehensive income (loss).

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