Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (15,463)	$ (17,311)
Other comprehensive income (loss), net of tax:
Unrealized gains (losses) on investments	(363)	254
Other comprehensive income (loss), net of tax	(363)	254
Comprehensive loss	$ (15,826)	$ (17,057)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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