Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jul. 31, 2018	Jul. 31, 2017	[2]	Jul. 31, 2018	Jul. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (39,207)	$ (26,032)	[1]	$ (65,169)	$ (53,738)	[1],[3]
Other comprehensive income (loss):
Net change in unrealized losses on available-for-sale securities	77	(12)		(48)	(12)	[2]
Foreign currency translation adjustments	(379)	181		(823)	249	[2]
Other comprehensive income (loss)	(302)	169		(871)	237	[2]
Comprehensive loss	$ (39,509)	$ (25,863)		$ (66,040)	$ (53,501)	[2]

[1] See Note 2 for a summary of adjustments.

[2] See Note 2 for a summary of adjustments.

[3] See Note 2 for a summary of adjustments.