Stock-based Compensation - Stock Option Activities (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
	Oct. 31, 2021 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding | shares	719,143
Shares, Granted | shares	14,700
Shares, Exercised | shares	(229,051)
Shares, Forfeited | shares	(7,401)
Shares, Expired | shares	(1,146)
Shares, Outstanding | shares	496,245
Shares, Exercisable | shares	411,465
Weighted-Average Exercise Price, Outstanding	$ 38.33
Weighted-Average Exercise Price, Granted	110.19
Weighted-Average Exercise Price, Exercised	25.37
Weighted-Average Exercise Price, Forfeited	69.40
Weighted-Average Exercise Price, Expired	9.86
Weighted-Average Exercise Price, Outstanding	46.05
Weighted-Average Exercise Price, Exercisable	42.64
Weighted-Average Grant-date Fair Value, Granted	$ 50.28
Total Intrinsic Value Of Options Exercised | $	$ 19,201
Weighted-Average Remaining Contractual Term, Outstanding	4 years 7 months 20 days
Weighted-Average Remaining Contractual Term, Exercisable	3 years 10 months 24 days
Aggregate Intrinsic Value, Outstanding | $	$ 69,365
Aggregate Intrinsic Value, Exercisable | $	$ 58,916