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

No definition available.

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- Definition

The total grant date fair value of equity settled awards determined by using valuation models.

+ References

No definition available.

+ Details

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- Definition

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).

+ References

No definition available.

+ Details

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- Definition

A roll forward of the weighted-average grant date fair value of equity settled awards.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested Number Modification

+ References

No definition available.

+ Details

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- Definition

Description of the method used for calculating number of awards under the plan.

+ References

No definition available.

+ Details

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- Definition

The number of units settled during the period.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

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).

+ References

+ Details

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- Definition

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

+ References

+ Details

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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.

+ References

+ Details

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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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.

+ Details

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- Definition

Net number of non-option equity instruments granted to participants.

+ References

+ Details

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- Definition

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

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ Details

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

+ References

+ Details

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- Definition

The number of employees affected by the modification of an equity-based compensation plan.

+ References

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

+ References

No definition available.

+ Details

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Stock-based compensation (VIDP) (Details 5) CAD / shares in Units, shares in Millions, CAD in Millions	12 Months Ended
	Dec. 31, 2016 CAD CAD / shares shares	Dec. 31, 2015 CAD CAD / shares shares	Dec. 31, 2014 CAD CAD / shares shares
Cash settled awards \| Deferred share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of the method used for calculating number of awards under the plan	For cash settled DSUs, the number of DSUs received by each participant is calculated using the Company’s average closing share price for the 20 trading days prior to and including the date of the incentive payment.
Voluntary Incentive Deferral Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
The number of years in the plan period over which the additional units will vest	4 years
Voluntary Incentive Deferral Plan [Member] \| Deferred share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Company's additional grant percentage of elected amount	25.00%
Incremental compensation cost from modification VIDP \| CAD		CAD 0.0
Voluntary Incentive Deferral Plan [Member] \| Equity settled awards \| Deferred share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of awards vested during the period VIDP \| CAD	CAD 1.0	CAD 1.0
Roll forward of the activity of deferred share units outstanding
Outstanding units at beginning of period	1.8
Granted	0.0
Vested	0.0
Settled	(0.3)
Outstanding units at end of period	1.5	1.8
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Grant Date Fair Value [Roll Forward]
Weighted-average grant date fair value outstanding units beginning of period \| CAD / shares	CAD 76.44	CAD 76.29
Weighted-average grant date fair value units granted DSUs \| CAD / shares	73.63
Weighted-average grant date fair value units vested during the year DSUs \| CAD / shares	81.71
Weighted-average grant date fair value of units settled during the period \| CAD / shares	76.35
Weighted-average grant date fair value outstanding units end of period \| CAD / shares	CAD 76.54	CAD 76.44	CAD 76.29
The grant date fair value of equity settled DSUs \| CAD	CAD 2.0
Aggregate intrinsic value of equity settled DSUs outstanding \| CAD	CAD 133.0
Voluntary Incentive Deferral Plan [Member] \| Cash settled awards \| Deferred share units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of cash settled DSUs modified to equity settled awards			1.7
Number of employees affected by modification to VIDP plan	104
Fair value of awards vested during the period VIDP \| CAD	CAD 0.0	CAD 0.0	CAD 0.0
Roll forward of the activity of deferred share units outstanding
Outstanding units at beginning of period	0.4
Granted	0.0
Vested	0.0
Settled	(0.1)
Outstanding units at end of period	0.3	0.4
Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Grant Date Fair Value [Roll Forward]
Stock-based compensation liability outstanding DSUs \| CAD	CAD 35.0	CAD 36.0
Stock price end of period \| CAD / shares	CAD 90.36