CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jul. 31, 2018	Jul. 31, 2017	Jul. 31, 2018	Jul. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss		$ (38,085)	$ (39,285)	$ (74,722)	$ (79,371)
Changes in foreign currency translation adjustment	[1]	(162)	149	(286)	178
Comprehensive loss		$ (38,247)	$ (39,136)	$ (75,008)	$ (79,193)

[1] Tax effect was not material