CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2017	Oct. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (24,216)	$ (19,535)	$ (69,985)	$ (64,861)
Other comprehensive (loss) income, net of tax:
Unrealized (loss) gain on available-for-sale securities	4	2	(33)	40
Foreign currency translation adjustments	21	(78)	181	(40)
Other comprehensive (loss) income	25	(76)	148	0
Total comprehensive loss	$ (24,191)	$ (19,611)	$ (69,837)	$ (64,861)

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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