Leases - Supplemental Balance Sheet Information Related to Leases (Detail) - USD ($) $ in Thousands	Apr. 30, 2021	Jan. 31, 2021
Operating Leases
Lease right-of-use assets	$ 53,776	$ 56,917
Lease liabilities	$ 11,184	$ 11,347
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Lease liabilities	Lease liabilities
Lease liabilities, noncurrent	$ 48,672	$ 51,393
Total operating lease liabilities	$ 59,856	$ 62,740
Weighted Average Remaining Lease Term	6 years 7 months 6 days	6 years 8 months 12 days
Weighted Average Discount Rate	3.80%	3.80%