Capital Stock - Additional Information (Detail) - USD ($)						12 Months Ended			68 Months Ended
	May 25, 2021	May 29, 2020	Mar. 16, 2020	May 29, 2019	Jun. 30, 2016	Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020	Jan. 31, 2022
Class Of Stock [Line Items]
Preference shares, shares authorized						20,000,000	20,000,000		20,000,000
Preference shares, par value						$ 0.00045	$ 0.00045		$ 0.00045
Preference shares, shares issued						0	0		0
Preference shares, shares outstanding						0	0		0
Amount authorized under stock repurchase program						$ 275,000,000.0			$ 275,000,000.0
Stock repurchase program, inception period					2016-06
Stock repurchased, shares									4,011,595
Stock repurchased during period, cash						0	$ 1,000,000	$ 0	$ 175,800,000
Stock Repurchase Program $50.0 Million Authorization [Member]
Class Of Stock [Line Items]
Stock repurchase program, authorization date				May 29, 2019
Stock repurchase program, expiration date				Jun. 30, 2020
Stock repurchased, shares			25,719
Stock repurchased during period, cash			$ 1,000,000.0
Amount available under stock repurchase program						$ 49,000,000.0			$ 49,000,000.0
Stock repurchase program, extended expiration period	12 months	12 months
Stock repurchase program, extended expiration date	Jun. 30, 2022	Jun. 30, 2021
Stock Repurchase Program $50.0 Million Authorization [Member] | Maximum [Member]
Class Of Stock [Line Items]
Amount authorized under stock repurchase program				$ 50,000,000.0