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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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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.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Topic 210
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
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-Name Accounting Standards Codification
-Topic 210
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- Definition

Fair value of financial and nonfinancial obligations.

+ References

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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

No definition available.

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- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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- Definition

Fair value portion of shares that an entity is required to redeem for cash or other assets at a fixed or determinable date or upon the occurrence of an event.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109262497&loc=d3e21216-110875

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- Definition

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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-Publisher FASB
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Financial instruments - Fair Value of Financial Instruments (Detail) $ in Thousands, $ in Thousands	Jun. 30, 2019 CAD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2018 CAD ($)	Dec. 31, 2018 USD ($)
Level 1
Fair Value of Financial Instruments [Line Items]
Long-term investment carried at fair value	$ 1,018,837		$ 814,530
Total financial assets		$ 1,018,837	814,530
Long-term debt		1,446,278		$ 768,400
Convertible debentures		627		639
Total financial liabilities		1,446,905		769,039
Level 2
Fair Value of Financial Instruments [Line Items]
Development loans and other receivables		12,294		110,019
Derivative financial instruments, assets		1,120		970
Total financial assets		13,414		110,989
Long-term debt		2,603,285		2,588,373
Convertible debentures		0
Derivative financial instruments, liabilities		89,370		102,785
Total financial liabilities		2,707,485		2,704,861
Level 2 \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		0
Level 2 \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	0
Level 2 \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		0
Level 2 \| Forward contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		1,120		869
Derivative financial instruments, liabilities	632
Level 2 \| Cross currency swap \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		76,532		93,198
Level 2 \| Foreign exchange forward \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,608
Level 2 \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		2,598		1,114
Level 2 \| Commodity contracts for regulatory operations \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				101
Level 2 \| Interest rate swaps \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities				8,473
Level 2 \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Convertible debentures				13,703
Preferred shares, Series C		14,830
Level 3
Fair Value of Financial Instruments [Line Items]
Development loans and other receivables		0		0
Long-term investment carried at fair value	78,824		$ 0
Derivative financial instruments, assets		80,997		61,838
Total financial assets		159,821		61,838
Derivative financial instruments, liabilities		88		57
Total financial liabilities		88		57
Level 3 \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		80,574		61,838
Derivative financial instruments, liabilities		63		57
Level 3 \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	423
Level 3 \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		25
Level 3 \| Forward contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				0
Portion at Other than Fair Value Measurement \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		200
Carrying amount
Fair Value of Financial Instruments [Line Items]
Development loans and other receivables		12,242		103,696
Long-term investment carried at fair value		1,097,661		814,530
Derivative financial instruments, assets		82,117		62,808
Total financial assets		1,192,020		981,034
Long-term debt		3,781,906		3,336,795
Convertible debentures		397		470
Derivative financial instruments, liabilities		89,458		102,842
Total financial liabilities		3,885,621		3,453,525
Carrying amount \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		80,574		61,838
Derivative financial instruments, liabilities		63		57
Carrying amount \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	423
Carrying amount \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		25
Carrying amount \| Forward contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		1,120
Derivative financial instruments, liabilities	632
Carrying amount \| Forward contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				869
Carrying amount \| Cross currency swap \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		76,532		93,198
Carrying amount \| Foreign exchange forward \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	9,608
Carrying amount \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		2,598		1,114
Carrying amount \| Commodity contracts for regulatory operations \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				101
Carrying amount \| Interest rate swaps \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities				8,473
Carrying amount \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Convertible debentures				13,418
Preferred shares, Series C		13,860
Fair value
Fair Value of Financial Instruments [Line Items]
Development loans and other receivables		12,294		110,019
Long-term investment carried at fair value		1,097,661		814,530
Derivative financial instruments, assets		82,117		62,808
Total financial assets		1,192,072		987,357
Long-term debt		4,049,563		3,356,773
Convertible debentures		627		639
Derivative financial instruments, liabilities		89,458		102,842
Total financial liabilities		4,154,478		3,473,957
Fair value \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		80,574		61,838
Derivative financial instruments, liabilities		63		57
Fair value \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets	423
Fair value \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		25
Fair value \| Forward contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets		1,120
Derivative financial instruments, liabilities	632
Fair value \| Forward contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				869
Fair value \| Cross currency swap \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		76,532		93,198
Fair value \| Foreign exchange forward \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities	$ 9,608
Fair value \| Commodity contracts for regulatory operations
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities		2,598		1,114
Fair value \| Commodity contracts for regulatory operations \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, assets				101
Fair value \| Interest rate swaps \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Derivative financial instruments, liabilities				8,473
Fair value \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Convertible debentures				$ 13,703
Preferred shares, Series C		$ 14,830