Income Taxes - Schedule of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2020	Jan. 31, 2019	Jan. 31, 2018
Income Tax Disclosure [Abstract]
Beginning balance	$ 37,531	$ 34,117	$ 37,977
Additions based on tax positions related to the current year	4,964	3,922	7,892
Additions for tax positions of prior years	252	109	28
Reductions for tax positions in prior years	0	(552)	(11,313)
Settlements for prior periods	0	0	0
Lapse of applicable statute of limitations	(52)	(65)	(467)
Ending balance	$ 42,695	$ 37,531	$ 34,117