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Fair Values (fair value of the Level 3 financial Liabilities) (Details) - Designated as Hedging Instrument [Member] CAD in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 CAD
Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Beginning Balance | CAD 277
Total realized and unrealized gains (losses) included in non-regulated operating revenues | 112
Net transfers out of Level 3 | 0
Ending Balance | 389
Regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Non-regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Regulatory Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Unrealized gains (losses) included in regulatory assets or liabilities | 0
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Beginning Balance | 0
Total realized and unrealized gains (losses) included in non-regulated operating revenues | 0
Net transfers out of Level 3 | 0
Ending Balance | 0
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Regulated fuel for generation and purchased power [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Non-regulated fuel for generation and purchased power [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Regulatory Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Unrealized gains (losses) included in regulatory assets or liabilities | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Natural Gas [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Beginning Balance | 279
Total realized and unrealized gains (losses) included in non-regulated operating revenues | 110
Net transfers out of Level 3 | 0
Ending Balance | 389
Cash Flow Hedging And Held for Trading Hedge [Member] | Natural Gas [Member] | Regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Natural Gas [Member] | Non-regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Natural Gas [Member] | Regulatory Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Unrealized gains (losses) included in regulatory assets or liabilities | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Beginning Balance | (2)
Total realized and unrealized gains (losses) included in non-regulated operating revenues | 2
Net transfers out of Level 3 | 0
Ending Balance | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Power [Member] | Regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Power [Member] | Non-regulated fuel for generation and purchased power [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Increase (reduction) in benefit included in regulated and nonregulated fuel for generation and purchased power | 0
Cash Flow Hedging And Held for Trading Hedge [Member] | Power [Member] | Regulatory Liabilities [Member] | Derivative Financial Instruments, Liabilities [Member] |
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |
Unrealized gains (losses) included in regulatory assets or liabilities | CAD 0

X
- Definition Total amount of unrealized (holding) gain (loss) and realized gain (loss) which is included in the statement of income (or changes in net liabilities) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). + References No definition available. + Details
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- Definition Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of financial instrument classified as a liability into (out of) level 3 of the fair value hierarchy. + References No definition available. + Details
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- Definition Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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