Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Deferred Tax Assets:
Accruals and reserves	$ 8,444	$ 11,022
Net operating loss carryforward	2,002	1,753
State income taxes	236	1,612
Tax credit carryforward	10,196	11,479
Other	30	264
Gross Deferred Tax Assets	20,908	26,130
Valuation Allowance	(10,329)	(9,670)
Total Deferred Tax Assets	10,579	16,460
Deferred Tax Liabilities:
Property and equipment	(633)	(906)
Intangible assets	(8,078)	(11,678)
Expensed internal-use software	(595)	(390)
Other	(1,611)
Total Deferred Tax Liabilities	(10,917)	(12,974)
Net Deferred Tax (Liability)	$ (338)
Net Deferred Tax Assets		$ 3,486