Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Apr. 30, 2020	Apr. 30, 2019
Income Statement [Abstract]
Revenue	$ 54,645	$ 47,188
Cost of revenue	22,625	19,335
Gross profit	32,020	27,853
Operating expenses:
Research and development	34,200	33,017
Selling, general and administrative	13,435	13,077
Total operating expenses	47,635	46,094
Loss from operations	(15,615)	(18,241)
Other income, net	1,278	2,196
Loss before income taxes	(14,337)	(16,045)
Provision for income taxes	1,126	1,266
Net loss	$ (15,463)	$ (17,311)
Net loss per share attributable to ordinary shareholders:
Basic	$ (0.45)	$ (0.53)
Diluted	$ (0.45)	$ (0.53)
Weighted-average shares used to compute net loss per share attributable to ordinary shareholders:
Basic	34,080,330	32,492,044
Diluted	34,080,330	32,492,044