Costs and payments related to employee benefits and equity-based compensation, such as pension expense and contributions, other postretirement benefits expense and payments, stock or unit options expense, and amortization of restricted stock or unit.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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No definition available.

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Subsequent Event Subsequent Event (Details) - CAD CAD in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Subsequent Event [Line Items]
Forfeited options		90,340
Subsequent Event [Member]
Subsequent Event [Line Items]
Forfeited options	752,145
Employee Benefits and Share-based Expense (Recovery)	CAD (51)
Performance Share Units [Member]
Subsequent Event [Line Items]
Forfeited cash settled awards		42,384	36,856
Performance Share Units [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Forfeited cash settled awards	22,514
Deferred Share Units [Member]
Subsequent Event [Line Items]
Forfeited cash settled awards		30,011	2,192
Deferred Share Units [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Forfeited cash settled awards	68,612