Common shares, treasury shares, reserves and dividends - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jan. 30, 2021	Feb. 01, 2020	Feb. 02, 2019
Class of Stock [Line Items]
Common shares, par value (usd per share)	$ 0.18	$ 0.18
Treasury stock reissued (in shares)	0.0	400,000	200,000
Treasury shares retired (in shares)	0
Cumulative undeclared dividends	$ 0.0
Series A Redeemable Convertible Preferred Stock
Class of Stock [Line Items]
Dividends on redeemable convertible preferred shares	$ 1.7	$ 1.7	$ 1.7

Cumulative Undeclared Redeemable Preferred Stock Dividends

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Treasury Stock, Shares Issued During Period, Net of Taxes and Forfeitures

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Face amount or stated value per share of common stock.

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Adjustment to retained earnings for the increase in carrying amount of redeemable preferred stock that is classified as temporary equity.

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Number of shares of common and preferred stock retired from treasury during the period.

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