Domestic Pension Plan as Percentage of Combined Pension Plan Assets

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- Definition

Domestic Pension Plan as Percentage of Combined Pension Plan Obligations

+ References

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- Definition

Expected Return On Fund Assets Calculated Using Market Related Assets Values Developed, Period

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- Definition

Maximum value of underlying asset represented by financial derivatives, excluding currency forwards.

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- Definition

Payments to employees, their beneficiaries or estates or to third-party benefit administrators.

+ References

No definition available.

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- Definition

Percentage of combined plan obligations, other benefit plans.

+ References

No definition available.

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- Definition

Percentage of defined benefit pension plan assets exposed to foreign currency risk.

+ References

No definition available.

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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.

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No definition available.

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

+ 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 (e)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

The amount of employer securities or securities of parties related to the employer that are included in plan assets.

+ 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 (n)
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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of 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
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- Definition

Amount included in accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan expected to be recognized in net periodic benefit (cost) credit for fiscal year following most recent annual statement of financial position.

+ References

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- Definition

Amount included in accumulated other comprehensive (income) loss for prior service cost (credit) expected to be recognized in net periodic benefit cost (credit) for fiscal year following most recent annual statement of financial position.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

The number of employer shares or related party shares included in plan assets.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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- Definition

Amount of cost for defined contribution plan.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
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- Definition

Amount of contributions made to multiemployer plan by employer.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
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Pensions and Other Benefits - Additional Information (Detail) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Period of average market values for calculating net periodic benefit cost	5 years
Target long term rate of return, net of all fees and expenses	7.75%	7.75%	7.75%
Maximum value of underlying assets represented by financial derivatives, excluding currency forwards	30.00%
Company's common shares in fund assets, Shares	107,330	109,630
Payments to employees, their beneficiaries or estates or to third-party benefit administrators	CAD 34	CAD 30	CAD 33
Net cost of defined contribution plan	9	9	9
Multi-employer plan contributions	5	4	CAD 4
Equity Securities [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Company's securities in fund assets	25	21
Debt Securities [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Company's securities in fund assets	CAD 1	3
US Dollar [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	40.00%
European Currencies [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	11.00%
Other Currency [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Plans exposure to foreign currency risk percentage	7.00%
Pension Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Defined benefit pension plans' accumulated benefit obligation	CAD 11,273	CAD 11,143
Unamortized actuarial loss expected to be recognized in next fiscal year	114
Unamortized prior service cost expected to be recognized in next fiscal year	3
Other Postretirement Benefit Plans, Defined Benefit [Member]
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Unamortized actuarial loss expected to be recognized in next fiscal year	3
Unamortized prior service cost expected to be recognized in next fiscal year	CAD 0
Canadian pension plans
Deferred Compensation Arrangement with Individual, Postretirement Benefits [Line Items]
Canadian pension plan as a percentage of combined plan assets	99.00%
Canadian pension plan as a percentage of combined plan obligations	98.00%
Canadian other benefits plans as a percentage of combined other plan obligations	96.00%