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

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-base Payment Award, Options, Vested and Nonvested Options Forfeited, Number of Shares

+ References

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

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5047-113901

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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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- Definition

Amount of cost (reversal of cost) for employee benefits and share-based payment arrangement. Includes, but is not limited to, pension, other postretirement, postemployment and termination benefits.

+ References

No definition available.

+ Details

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- Definition

Amount of cost (reversal of cost) for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(4))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(b)(2))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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

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

+ References

No definition available.

+ Details

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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- Definition

Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

+ References

No definition available.

+ Details

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Stock-Based Compensation - Narrative (Details) - CAD ($) $ / shares in Units, $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Stock-based compensation expense (recovery)	$ 14	$ (12)
Employee Stock Options
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Number of options issued (shares)	169,968
Weighted average exercise price on the grant date	$ 231.59
Expiration period	7 years
Grant date fair value, options	$ 9
Employee Stock Options \| Minimum [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	12 months
Employee Stock Options \| Maximum [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	48 months
Performance Shares [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	3 years
Units issued	123,798
Grant date fair value	$ 29
PSU payout percentage			160.00%
Number of trading days			30 days
PSU payout	$ 30
PSUs vested in the period	82,800
Deferred Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period	48 months
Units issued	7,314
Grant date fair value	$ 2
Chief Executive Officer [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Compensation and benefits		(51)
Pension benefits		$ (27)
Chief Executive Officer [Member] \| Employee Stock Options
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Forfeited vested and unvested options		752,145
Chief Executive Officer [Member] \| Performance Shares [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Forfeited awards other than options		22,514
Chief Executive Officer [Member] \| Deferred Share Units [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Forfeited awards other than options		68,612