Percentage of additional units granted by Company based on the amount elected by participant.

No definition available.

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The weighted average fair value at grant date for outstanding equity-based awards 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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No definition available.

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- Definition

The stock-based compensation liability outstanding related to deferred share units.

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No definition available.

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The number of units settled during the period.

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No definition available.

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The weighted-average grant date fair value of units settled during the period.

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No definition available.

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- Definition

Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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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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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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The weighted average fair value at grant date for nonvested equity-based awards issued 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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- 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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Net number of non-option equity instruments granted to participants.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Intrinsic value of outstanding award under share-based payment arrangement. Excludes share and unit options.

+ References

No definition available.

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Stock-based Compensation (VIDP) (Details) - CAD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Weighted-average grant date fair value
Remittance of stock-based award participants' withholding tax obligation	$ 44	$ 37	$ 48
Closing stock price (in dollars per share)	$ 160.84
Voluntary Incentive Deferral Plan (VIDP) [Member] \| DSU [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company's additional grant percentage of elected amount	25.00%
Number of years in the plan period over which the units will vest	4 years
Voluntary Incentive Deferral Plan (VIDP) [Member] \| Equity Settled Awards [Member] \| DSU [Member]
Roll forward of outstanding DSUs
Units outstanding at beginning of period (in shares)	0.5
Granted (in shares)	0.1
Settled (in shares)	(0.3)
Units outstanding at end of period (in shares)	0.3	0.5
Weighted-average grant date fair value
Weighted-average grant date fair value at beginning of period (in dollars per share)	$ 87.24
Weighted-average grant date fair value of units granted in period (in dollars per share)	159.13
Weighted-average grant date fair value of units settled in period (in dollars per share)	83.28
Weighted-average grant date fair value at end of period (in dollars per share)	$ 106.60	$ 87.24
Aggregate intrinsic value of share units outstanding	$ 51
Remittance of stock-based award participants' withholding tax obligation	20
Voluntary Incentive Deferral Plan (VIDP) [Member] \| Cash Settled Awards [Member] \| DSU [Member]
Weighted-average grant date fair value
Stock-based compensation liability outstanding	$ 7	$ 9
Closing stock price (in dollars per share)	$ 160.84	$ 155.38