The cash settled restricted share units compensation expense.

No definition available.

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- Definition

The deferred share units compensation expense.

+ References

No definition available.

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- Definition

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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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 6
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- Definition

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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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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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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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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- Definition

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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Stock-Based Compensation Plans - Additional information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2022	Jul. 31, 2021	Jan. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost	$ 700,000		$ 700,000		$ 700,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance (in shares)	1,627,978		1,627,978		1,319,279
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)			354,699
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 200,000	$ 1,400,000	$ 1,300,000	$ 2,000,000.0
Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	10,500,000		$ 10,500,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			2 years 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value			$ 100,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	10,200,000		$ 10,200,000
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, Equity Instruments Other than Options, Vested in Period, Fair Value	0		$ 5,200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	5,600,000		$ 5,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)			1 year 10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value	$ 0		$ 0
Shareholder-Approved Stock Options Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in shares)	2,700,683		2,700,683
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	$ 1,627,978		$ 1,627,978
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)	92,422	1,000	354,699	269,025
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)			$ 18.91	$ 16.85
Deferred Share Unit Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Deferred Share Units Outstanding Number (in shares)	281,768		281,768		252,011
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	$ 18,500,000		$ 18,500,000		$ 18,300,000
Deferred Share Units Grants In Period (in shares)			29,757
Deferred Share Units Compensation Expense	2,700,000	$ 3,000,000.0	$ 300,000	$ 3,200,000
Cash-Settled Restricted Share Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total	1,100,000		1,100,000		1,000,000.0
Deferred Compensation Share-based Arrangements, Liability, Current and Noncurrent	600,000		600,000		$ 800,000
Cash Settled Restricted Share Units Compensation Expense	$ 200,000	$ 300,000	$ 400,000	$ 600,000