Financial instruments - Fair Value of Financial Instruments (Detail) - CAD CAD in Thousands	Dec. 31, 2015	Dec. 31, 2014
Level 1
Fair Value of Financial Instruments [Line Items]
Long-term debt	CAD 511,829	CAD 520,142
Total financial liabilities	511,829	520,142
Level 2
Fair Value of Financial Instruments [Line Items]
Notes receivable	126,468	41,339
Derivative financial instruments, assets	4	0
Total financial assets	126,472	41,339
Long-term debt	1,035,517	843,792
Preferred shares, Series C	17,303	18,209
Derivative financial instruments, liabilities	114,812	45,271
Total financial liabilities	1,167,632	907,272
Level 3
Fair Value of Financial Instruments [Line Items]
Notes receivable	0	0
Derivative financial instruments, assets	88,357	42,470
Total financial assets	88,357	42,470
Derivative financial instruments, liabilities	446	0
Total financial liabilities	446	0
Energy contracts \| Designated as a hedge \| Cash flow hedge \| Level 3
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	88,357	41,966
Derivative financial instruments, liabilities	446
Energy contracts \| Not designated as a hedge \| Cash flow hedge \| Level 3
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		504
Cross currency swap \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	101,559
Cross currency swap \| Designated as a hedge \| Net Investment Hedging \| Level 2
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	101,559	36,276
Interest rate swaps
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,659
Interest rate swaps \| Designated as a hedge \| Level 2
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,659	4,684
Interest rate swaps \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		1,383
Interest rate swaps \| Not designated as a hedge \| Level 2
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		1,383
Foreign exchange forward \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	1,918
Foreign exchange forward \| Not designated as a hedge \| Level 2
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	1,918
Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	2,122
Commodity contracts for regulatory operations \| Level 2
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	4
Derivative financial instruments, liabilities	1,676	2,928
Carrying amount
Fair Value of Financial Instruments [Line Items]
Notes receivable	119,383	39,510
Derivative financial instruments, assets	88,361	42,470
Total financial assets	207,744	81,980
Long-term debt	1,486,795	1,271,719
Preferred shares, Series C	18,527	18,693
Derivative financial instruments, liabilities	115,258	45,271
Total financial liabilities	1,620,580	1,335,683
Carrying amount \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	88,357	41,966
Derivative financial instruments, liabilities	446
Carrying amount \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		504
Carrying amount \| Cross currency swap \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	101,559	36,276
Carrying amount \| Interest rate swaps \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,659	4,684
Carrying amount \| Interest rate swaps \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		1,383
Carrying amount \| Foreign exchange forward \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	1,918
Carrying amount \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	4
Derivative financial instruments, liabilities	1,676	2,928
Fair Value
Fair Value of Financial Instruments [Line Items]
Notes receivable	126,468	41,339
Derivative financial instruments, assets	88,361	42,470
Total financial assets	214,829	83,809
Long-term debt	1,547,346	1,363,934
Preferred shares, Series C	17,303	18,209
Derivative financial instruments, liabilities	115,258	45,271
Total financial liabilities	1,679,907	1,427,414
Fair Value \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	88,357	41,966
Derivative financial instruments, liabilities	446
Fair Value \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		504
Fair Value \| Cross currency swap \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	101,559	36,276
Fair Value \| Interest rate swaps \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,659	4,684
Fair Value \| Interest rate swaps \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		1,383
Fair Value \| Foreign exchange forward \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	1,918
Fair Value \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	4
Derivative financial instruments, liabilities	CAD 1,676	CAD 2,928

Fair Value of Financial Instruments [Line Items]

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- Definition

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

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fair value of financial and nonfinancial obligations.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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