Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Changes in Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Allowance for doubtful accounts, beginning balance	$ 2,000	$ 944	$ 210
Provision, net	482	1,394	918
Writeoffs	(1,420)	(338)	(184)
Allowance for doubtful accounts, ending balance	$ 1,062	$ 2,000	$ 944