Pensions and other postretirement benefits (Details 9) (CAD) In Millions, unless otherwise specified	Dec. 31, 2014
Pensions [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
2015	1,011
2016	1,034
2017	1,048
2018	1,059
2019	1,067
Years 2020 to 2024	5,379
Other postretirement benefits [Member]
Defined Benefit Plan Estimated Future Benefit Payments [Line Items]
2015	17
2016	17
2017	18
2018	18
2019	18
Years 2020 to 2024	81

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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- Definition

Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

+ References

+ Details

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

+ References

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