XML 133 R116.htm IDEA: XBRL DOCUMENT v3.7.0.1

Fair Values (Quantitative Information Significant Unobservable Inputs - Assets & Liabilities) (Details) - Designated as Hedging Instrument [Member] - CAD CAD / shares in Units, CAD in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 40.0	CAD 51.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	389.0	277.0
Derivative Assets (Liabilities), at Fair Value, Net, Total	(349.0)	(226.0)
Held for Trading Hedge [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure		54.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	0.0
Held for Trading Hedge [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	CAD 3.0
Held for Trading Hedge [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure		CAD 3.0
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 1.25
Fair Value Inputs, Comparability Adjustments		(0.06%)
Fair Value Inputs, Probability of Default		0.00%
Fair Value Inputs, Discount Rate		0.00%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 15.74
Fair Value Inputs, Comparability Adjustments		0.95%
Fair Value Inputs, Probability of Default		0.09%
Fair Value Inputs, Discount Rate		0.08%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 6.19
Fair Value Inputs, Comparability Adjustments		0.68%
Fair Value Inputs, Probability of Default		0.00%
Fair Value Inputs, Discount Rate		0.00%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 1.83	CAD 46.45
Fair Value Inputs, Comparability Adjustments	(0.11%)
Fair Value Inputs, Probability of Default	0.00%
Fair Value Inputs, Entity Credit Risk		0.06%
Fair Value Inputs, Discount Rate	0.00%	0.00%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 11.87	CAD 103.27
Fair Value Inputs, Comparability Adjustments	0.64%
Fair Value Inputs, Probability of Default	0.05%
Fair Value Inputs, Entity Credit Risk		0.06%
Fair Value Inputs, Discount Rate	0.10%	4.15%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 5.93	CAD 70.69
Fair Value Inputs, Comparability Adjustments	0.27%
Fair Value Inputs, Probability of Default	0.01%
Fair Value Inputs, Entity Credit Risk		0.06%
Fair Value Inputs, Discount Rate	0.01%	0.47%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 1.13
Fair Value Inputs, Probability of Default		0.00%
Fair Value Inputs, Discount Rate		0.00%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 9.12
Fair Value Inputs, Probability of Default		0.10%
Fair Value Inputs, Discount Rate		0.33%
Held for Trading Hedge [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes		CAD 3.26
Fair Value Inputs, Probability of Default		0.01%
Fair Value Inputs, Discount Rate		0.04%
Held for Trading Hedge [Member] | Physical natural gas purchases and sales [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 12.0
Held for Trading Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Probability of Default		0.01%
Held for Trading Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 1.83	CAD 5.15
Fair Value Inputs, Comparability Adjustments	(0.11%)
Fair Value Inputs, Probability of Default	0.00%
Fair Value Inputs, Discount Rate	0.00%
Held for Trading Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 11.87	6.21
Fair Value Inputs, Comparability Adjustments	0.64%
Fair Value Inputs, Probability of Default	0.05%
Fair Value Inputs, Discount Rate	0.10%
Held for Trading Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 6.16	CAD 5.72
Fair Value Inputs, Comparability Adjustments	0.39%
Fair Value Inputs, Probability of Default	0.00%	0.01%
Fair Value Inputs, Discount Rate	0.00%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 0.0	CAD (8.0)
Financial and Nonfinancial Liabilities, Fair Value Disclosure	CAD 0.0	CAD (2.0)
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 19.7	CAD 26.27
Fair Value Inputs, Correlation factor		0.98%
Fair Value Inputs, Entity Credit Risk	0.00%	0.00%
Fair Value Inputs, Discount Rate	0.09%	0.00%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 76.94	CAD 129.2
Fair Value Inputs, Correlation factor		1.00%
Fair Value Inputs, Entity Credit Risk	0.02%	0.02%
Fair Value Inputs, Discount Rate	0.02%	0.15%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 33.48	CAD 70.82
Fair Value Inputs, Correlation factor		0.99%
Fair Value Inputs, Entity Credit Risk	0.01%	0.00%
Fair Value Inputs, Discount Rate	0.03%	0.01%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 19.7	CAD 26.27
Fair Value Inputs, Correlation factor		0.98%
Fair Value Inputs, Probability of Default	0.00%	0.00%
Fair Value Inputs, Discount Rate	0.02%	0.00%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 76.94	CAD 129.2
Fair Value Inputs, Correlation factor		1.00%
Fair Value Inputs, Probability of Default	0.01%	0.02%
Fair Value Inputs, Discount Rate	0.09%	0.15%
Held for Trading Hedge [Member] | Power swaps and physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 33.37	CAD 70.45
Fair Value Inputs, Correlation factor		0.99%
Fair Value Inputs, Probability of Default	0.00%	0.00%
Fair Value Inputs, Discount Rate	0.03%	0.01%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 27.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	CAD 386.0	CAD 279.0
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Entity Credit Risk		0.00%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 1.55	CAD 0.74
Fair Value Inputs, Probability of Default		0.00%
Fair Value Inputs, Entity Credit Risk	0.00%
Fair Value Inputs, Discount Rate	0.00%	0.00%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 11.87	CAD 10.59
Fair Value Inputs, Probability of Default		0.03%
Fair Value Inputs, Entity Credit Risk	0.70%
Fair Value Inputs, Discount Rate	0.14%	0.07%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Liabilities [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 6.26	CAD 5.58
Fair Value Inputs, Probability of Default		0.00%
Fair Value Inputs, Entity Credit Risk	0.00%	0.00%
Fair Value Inputs, Discount Rate	0.02%	0.01%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 1.41
Fair Value Inputs, Probability of Default	0.00%
Fair Value Inputs, Discount Rate	0.00%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 11.87
Fair Value Inputs, Probability of Default	7.00%
Fair Value Inputs, Discount Rate	0.32%
Held for Trading Hedge [Member] | Natural gas swaps, futures, forwards, physical contracts [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 3.87	CAD 5.56
Fair Value Inputs, Probability of Default	0.01%	0.46%
Fair Value Inputs, Discount Rate	0.05%	5.28%
Regulatory Deferral Hedge [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Financial and Nonfinancial Liabilities, Fair Value Disclosure	CAD 0.0
Regulatory Deferral Hedge [Member] | Heavy fuel oil purchases [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	1.0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	CAD 0.0
Regulatory Deferral Hedge [Member] | Heavy fuel oil purchases [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Probability of Default	0.80%
Regulatory Deferral Hedge [Member] | Heavy fuel oil purchases [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 0
Regulatory Deferral Hedge [Member] | Heavy fuel oil purchases [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	69.64
Regulatory Deferral Hedge [Member] | Heavy fuel oil purchases [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 69.64
Fair Value Inputs, Probability of Default	0.80%
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 0.0	CAD 2.0
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Probability of Default	0.01%
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Minimum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 4.75
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Maximum [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	4.94
Regulatory Deferral Hedge [Member] | Physical natural gas purchases and sales [Member] | Market Approach Valuation Technique [Member] | Fair Value, Inputs, Level 3 [Member] | Derivative Financial Instruments, Assets [Member] | Weighted Average [Member]
Fair Value Inputs [Abstract]
Fair Value Inputs, Offered Quotes	CAD 4.87
Fair Value Inputs, Probability of Default	0.01%
Cash Flow Hedging [Member] | Power swaps and physical contracts [Member]
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Line Items]
Assets, Fair Value Disclosure	CAD 0.0

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ 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 (a)
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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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Percentage of adjustment to the observed price for a similar asset or liability when an identical transaction does not exist, used as an input to measure fair value.

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-Publisher FASB
-Name Accounting Standards Codification
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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Risk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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Price at which a dealer is willing to buy an instrument, used as an input to measure fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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-Section 50
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Percentage of likelihood a loan will not be repaid and instead default, used as an input to measure fair value.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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Fair value of financial and nonfinancial obligations.

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-SubTopic 10
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