Number of additional Performance Deferred Share Units that can be granted as a percentage of units originally granted

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- Definition

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

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No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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-Name Accounting Standards Codification
-Topic 718
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- Definition

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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- Definition

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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- Definition

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

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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.

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No definition available.

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- Definition

Number of non-option equity instruments exercised by participants.

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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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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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- Definition

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

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- Definition

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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- Definition

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

+ References

No definition available.

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Stock-Based Compensation - Narrative (Details) - CAD ($) $ / shares in Units, $ in Millions	3 Months Ended			6 Months Ended		12 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 43		$ 39	$ 54	$ 73
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options issued				215,943
Weighted-average grant price				$ 350.65
Expiration period				7 years
Stock options grant date fair value				$ 15
Stock Options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				12 months
Stock Options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				48 months
Performance Share Units (PSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued				97,710
Grant date fair value				$ 34
PSU payout percentage						193.00%
Number of trading days						30 days
Cash payout		$ 76
Units paid in period		121,225
Performance Deferred Share Units (PDSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units issued				10,029
Grant date fair value				$ 4
Number of additional PDSUs that can be granted as a percentage of original units granted	25.00%			25.00%
PSUs and PDSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Deferred Share Units (DSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				48 months
Units issued				15,430
Grant date fair value				$ 5
Cash payout				$ 7
Units paid in period				21,762