Pensions and other postretirement benefits (Details 6) (Pensions [Member], CAD) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Pensions [Member]
Information for the pension plans with an accumulated benefit obligation in excess of plan assets [Abstract]
Projected Benefit Obligation	646	527
Accumulated benefit obligation	585	475
Fair value of plan assets	246	224

Projected Benefit Obligation For Pension Plans With Abo In Excess Of Plan Assets

No definition available.

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- Details

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 55

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=32704760&loc=d3e4179-114921

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e2417-114920

+ Details

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- Definition

If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

+ Details

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