The difference between the accumulated benefit obligation and fair value of plan assets.

No definition available.

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- Definition

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

+ References

No definition available.

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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 less the aggregate fair value of plan assets as of the measurement date of each statement of financial position presented.

+ References

No definition available.

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- Definition

For defined benefit pension plans, the actuarial present value of benefits (whether vested or nonvested) attributed by the pension benefit formula to employee service rendered before a specified date and based on employee service and compensation (if applicable) before that date. The accumulated benefit obligation differs from the projected benefit obligation in that it includes no assumption about future compensation levels. For plans with flat-benefit or nonpay-related pension benefit formulas, the accumulated benefit obligation and the projected benefit obligation are the same.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accumulated Benefit Obligation
-URI http://asc.fasb.org/extlink&oid=6503844

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-Section 50
-Paragraph 1
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=65897934&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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 30
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6520858

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- References

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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

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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

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

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 3
-Subparagraph (a)
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- Definition

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

+ References

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

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-Name Accounting Standards Codification
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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

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-Publisher FASB
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- Definition

This represents the entire liability recognized in the balance sheet that is associated with the defined benefit plans.

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EMPLOYEE POST-RETIREMENT BENEFITS - Obligations, Fair Value and Weighted Average Assets (Details) - CAD CAD in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Funded status based on accumulated benefit obligation
Plan assets at fair value	CAD 3,562	CAD 2,636
Pension plans' weighted average asset allocations and target allocations by asset category
Percentage of Plan Assets	100.00%	100.00%
Pension Benefit Plans
Benefit obligation and fair value of plan assets for plans that are not fully funded
Projected benefit obligation	CAD (3,456)	CAD (2,780)
Plan assets at fair value	3,208	2,591
Funded Status – Plan Deficit	(248)	(189)
Funded status based on accumulated benefit obligation
Accumulated benefit obligation	(3,202)	(2,600)
Plan assets at fair value	3,208	2,591	CAD 2,398
Funded Status – Plan Surplus/(Deficit)	6	(9)
Accumulated benefit obligation and fair value of plan assets for plans that are not fully funded
Accumulated benefit obligation	(990)	(807)
Plan assets at fair value	868	680
Funded Status – Plan Deficit	CAD (122)	CAD (127)
Pension plans' weighted average asset allocations and target allocations by asset category
Percentage of Plan Assets	100.00%	100.00%
Pension Benefit Plans \| Debt securities
Pension plans' weighted average asset allocations and target allocations by asset category
Percentage of Plan Assets	31.00%	34.00%
Amount of debt or common shares included in plan assets	CAD 9	CAD 2
Percentage of Plan Assets	0.20%	0.10%
Pension Benefit Plans \| Debt securities \| Minimum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	25.00%
Pension Benefit Plans \| Debt securities \| Maximum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	40.00%
Pension Benefit Plans \| Equity securities
Pension plans' weighted average asset allocations and target allocations by asset category
Percentage of Plan Assets	63.00%	66.00%
Amount of debt or common shares included in plan assets	CAD 4	CAD 4
Percentage of Plan Assets	0.10%	0.10%
Pension Benefit Plans \| Equity securities \| Minimum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	45.00%
Pension Benefit Plans \| Equity securities \| Maximum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	75.00%
Pension Benefit Plans \| Alternatives
Pension plans' weighted average asset allocations and target allocations by asset category
Percentage of Plan Assets	6.00%	0.00%
Pension Benefit Plans \| Alternatives \| Minimum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	5.00%
Pension Benefit Plans \| Alternatives \| Maximum
Pension plans' weighted average asset allocations and target allocations by asset category
Target Allocations	15.00%
Other Post-Retirement Benefit Plans
Benefit obligation and fair value of plan assets for plans that are not fully funded
Projected benefit obligation	CAD (207)	CAD (198)
Plan assets at fair value	0	0
Funded Status – Plan Deficit	(207)	(198)
Funded status based on accumulated benefit obligation
Plan assets at fair value	CAD 354	CAD 45	CAD 39