Stock-based Compensation Plans - Additional information (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jan. 31, 2022	Jan. 31, 2021	Jan. 31, 2020
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	$ 0.7	$ 0.7
Share-based Payment Arrangement, Exercise of Option, Tax Benefit	$ 0.1		$ 0.1
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)	1,319,279	1,147,720	1,127,822
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	271,025	381,859	367,173
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 16.77	$ 10.19	$ 8.99
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 3.7	$ 10.8	$ 2.0
Share-based Payment Arrangement, Option [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 6.1
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	2 years 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 3.4
Performance Shares [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 6.7
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 1 month 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 3.6
Restricted Stock Units (RSUs) [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 3.2
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)	1 year 7 months 6 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 2.6
Shareholder-Approved Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)	1,319,279
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	271,025	381,859
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)	$ 16.77	$ 10.19
Shareholder-Approved Stock Option Plan [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	3,041,719
Deferred Share Unit Plan [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 0.0	$ 0.0
Deferred Share Units Outstanding Number (in shares)	252,011	226,525
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	$ 18.3	$ 13.8
Deferred Share Units Grants In Period (in shares)	25,486
Deferred Share Units Redeemed and Settled in Cash (in shares)	0
Deferred Share Units Compensation Expense	$ 4.5	4.6	5.0
Cash-Settled Restricted Share Unit [Member]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	1.0	1.5
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	0.8	0.9
Cash Settled Restricted Share Units Compensation Expense	$ 1.3	$ 1.1	$ 0.9

The cash settled restricted share units compensation expense.

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The deferred share units compensation expense.

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No definition available.

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The number of deferred share units granted in period.

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No definition available.

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Number of outstanding deferred share units as of the reported date.

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Represents the number of deferred share units redeemed and settled in cash.

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Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of tax benefit from exercise of option under share-based payment arrangement.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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