Restructuring Charges - Summary of Activities Related to the Restructuring Plan (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018		Jan. 31, 2017	Jan. 31, 2016
Restructuring And Related Activities [Abstract]
Balance as of January 31, 2017	$ 0
Gross charges	1,873
Cash payments	(810)
Restructuring charges	(974)	[1]	$ 0	$ 0
Balance as of January 31, 2018	$ 89		$ 0

[1] The non-cash adjustments to restructuring charges primarily consist of the reversal of previously recognized stock-based compensation expense related to awards that will not vest and the reversal of incentive compensation that will not be paid as a result of the restructuring plan.