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Employee Benefit Plans (Plans with PBO/APBO in excess of Plan assets) (Details) - CAD CAD in Millions | Dec. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Pension Plan [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Aggregate Projected Benefit Obligation | CAD 2,579 | CAD 1,489
Aggregate Fair Value of Plan Assets | 2,171 | 1,261
Funded Status | (408) | (228)
Non-pension Benefit Plans [Member |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Aggregate Projected Benefit Obligation | 358 | 87
Aggregate Fair Value of Plan Assets | 39 | 5
Funded Status | CAD (319) | CAD (82)

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- Definition If aggregate disclosures are presented, the aggregate funded status is measured as the difference between the fair value of plan assets and the benefit obligation. Will normally be the same as the net Defined Benefit Plan, Amounts Recognized in Balance Sheet, Total. + References No definition available. + Details
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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. + References No definition available. + 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 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=73719040&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=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate projected 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 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 Reference 2: 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=73719040&loc=d3e4179-114921 + Details
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