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Share Based Compensation Arrangement By Share Based Payment Award Grant Date Fair Value

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Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Ownership Target, Period

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Share-based Compensation Arrangement by Share-based Payment Award, Ratio Employer Match Per Dollar Contributed

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Share-based Compensation Arrangement by Share-based Payment Award, Trading Days Used to Calculate Average Share Price

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Amount of cash paid to settle liability for award under share-based payment arrangement.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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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.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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Number of shares purchased for issuance under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Value, before forfeiture, of shares granted under share-based payment arrangement. Excludes employee stock ownership plan (ESOP).

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Stock-based compensation - Narrative (Details) $ in Millions		3 Months Ended	6 Months Ended	12 Months Ended
	Apr. 21, 2021	Mar. 31, 2021 CAD ($) shares	Jun. 30, 2021 CAD ($) shares	Dec. 31, 2021 CAD ($) shares	Dec. 31, 2020 CAD ($) shares	Dec. 31, 2019 CAD ($) shares	Dec. 31, 2018 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 131.0	$ 170.0	$ 133.0
Stock based compensation expense, tax benefit				29.0	42.0	33.0
Stock split ratio	5
Share-based liabilities paid				126.0	86.0	58.0
Regular and Performance Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 23.0	16.0	14.0
Expiration period				7 years
Fair value of options at grant date				$ 26.0	15.0	14.0
Unrecognized compensation expense				$ 16.0
Weighted-average period of recognition for unrecognized compensation				10 months 24 days
Fair value of shares vested for stock option plan				$ 18.0	$ 10.0	$ 8.0
Regular and Performance Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				12 months
Regular and Performance Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				48 months
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued (in shares) \| shares				431,430	489,990	668,405
Grant date fair value				$ 37.0
Share-based liabilities paid				$ 119.0	$ 76.0	$ 54.0
Performance Deferred Share Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued (in shares) \| shares				12,694	50,145
Grant date fair value				$ 1.0
Matching % of DSU's granted to senior managers				25.00%
PSUs and PDSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 91.0	$ 121.0	89.0
Vesting period				3 years
Unrecognized compensation expense				$ 35.0
Weighted-average period of recognition for unrecognized compensation				1 year 4 months 24 days
Units issued (in shares) \| shares				444,124	540,135
DSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 6.0	$ 21.0	20.0
Vesting period				36 months
Unrecognized compensation expense				$ 1.0
Weighted-average period of recognition for unrecognized compensation				1 year
Units issued (in shares) \| shares				70,112	95,204
Grant date fair value				$ 6.0
Matching % of DSU's granted to senior managers				25.00%
Number of trading days				10 days
Share-based liabilities paid				$ 1.0	$ 9.0	4.0
Ownership target period				5 years
Employee Share Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense				$ 8.0	$ 7.0	$ 6.0
Vesting period				1 year
Employer matching ratio per dollar contributed				0.3333
Maximum percentage of annual salary that an employee can contribute				6.00%
Number of shares purchased on behalf of participants \| shares				538,022	576,720	689,710
Employer contributions				$ 11.0	$ 9.0	$ 8.0
Share-based Payment Arrangement, Tranche One \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued (in shares) \| shares		570,056					626,400
Payout percentage				200.00%	200.00%
PSUs vested in period (in shares) \| shares				630,129
Fair value of PSUs vested in period				$ 116.0
Number of trading days				30 days	30 days
Share-based liabilities paid		$ 98.0
Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based liabilities paid			$ 21.0
Share-based Payment Arrangement, Tranche Two \| PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued (in shares) \| shares			173,456	2,895		2,895	184,875
Payout percentage					125.00%
Number of trading days					30 days