Unrealized loss on foreign exchange forward contracts

No definition available.

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- Definition

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners).

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

Name:	us-gaap_ForeignCurrencyDerivativesAbstract
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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

+ Details

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- References

No definition available.

+ Details

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- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References

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

+ Details

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- Details

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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeForwardMember
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Financial instruments (Details 1) CAD in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2016 CAD	Dec. 31, 2015 CAD	Dec. 31, 2014 CAD	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2013 CAD
Interest rate derivatives [Abstract]
Accumulated other comprehensive income (loss), unamortized gain (loss) relating to treasury stock, after tax	CAD (3,145)	CAD (2,406)	CAD (2,961)			CAD (2,040)
Derivative instruments [Member]
Interest rate derivatives [Abstract]
Accumulated other comprehensive income (loss), unamortized gain (loss) relating to treasury stock, after tax	7	7	7			CAD 8
Foreign Exchange Forward [Member]
Foreign currency derivatives [Abstract]
Gain (Loss) on foreign exchange forward contracts net pretax	(1)	61	CAD 9
Foreign exchange forward contracts notional amount \| $				$ 1,035	$ 361
Unrealized gain on foreign exchange forward contracts	19	4
Unrealized loss on foreign exchange forward contracts	CAD 1	CAD 2