Components of Net Periodic Benefit Cost (Detail) - CAD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
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Pension benefits | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Current service cost | $ 60 | $ 54 | $ 120 | $ 109 |
Interest cost | 75 | 79 | 151 | 158 |
Expected return on plan assets | (100) | (101) | (201) | (202) |
Amortization of prior service cost | 1 | 2 | 2 | 5 |
Amortization of actuarial loss (gain) | 43 | 45 | 87 | 89 |
Net periodic benefit cost | 79 | 79 | 159 | 159 |
Other postretirement benefits | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Current service cost | 4 | 4 | 8 | 8 |
Interest cost | 6 | 6 | 11 | 12 |
Amortization of actuarial loss (gain) | 1 | 2 | 3 | 4 |
Net periodic benefit cost | $ 11 | $ 12 | $ 22 | $ 24 |
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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. No definition available.
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- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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