Financial instruments - Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value of Financial Instruments [Line Items]
Notes payable to related party	$ 25,808	$ 30,493
Interest rate swaps designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	7,015
Cross-currency swap designated as a net investment hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	55,543
Level 1
Fair Value of Financial Instruments [Line Items]
Long-term investments carried at fair value	1,753,210	1,708,683
Total financial assets	1,753,210	1,708,683
Long-term debt	2,418,580	2,316,586
Convertible debentures	519	623
Total financial liabilities	2,419,099	2,317,209
Level 2
Fair Value of Financial Instruments [Line Items]
Long-term investments carried at fair value		20,015
Development loans and other receivables	33,286	31,088
Total derivative instruments	5,260	194
Total financial assets	38,546	51,297
Long-term debt	4,125,352	2,823,473
Notes payable to related party	25,808	30,493
Convertible debentures	0
Total derivative instruments	58,614	104,481
Total financial liabilities	4,224,354	2,974,012
Level 2 \| Interest rate swaps designated as a hedge \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,581
Total derivative instruments	7,008	19,649
Level 2 \| Commodity contracts for regulated operations
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,721	194
Total derivative instruments	1,348	614
Level 2 \| Cross-currency swap designated as a net investment hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,958
Level 2 \| Cross-currency swap designated as a net investment hedge \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	50,258	84,218
Level 2 \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Preferred shares, Series C	14,580	15,565
Level 3
Fair Value of Financial Instruments [Line Items]
Long-term investments carried at fair value	95,246	110,514
Development loans and other receivables		0
Total derivative instruments	15,362	51,913
Total financial assets	110,608	162,427
Total derivative instruments	61,631	5,929
Total financial liabilities	61,631	5,929
Level 3 \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	15,362	51,525
Total derivative instruments	60,462	5,597
Level 3 \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,169
Level 3 \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments		388
Total derivative instruments		332
Carrying amount
Fair Value of Financial Instruments [Line Items]
Long-term investments carried at fair value	1,848,456	1,839,212
Development loans and other receivables	32,261	23,804
Total derivative instruments	20,622	52,107
Total financial assets	1,901,339	1,915,123
Long-term debt	6,211,375	4,538,470
Notes payable to related party		30,493
Convertible debentures	277	295
Total derivative instruments	120,245	110,410
Total financial liabilities	6,371,053	4,693,366
Carrying amount \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	15,362	51,525
Total derivative instruments	60,462	5,597
Carrying amount \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,169
Carrying amount \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments		388
Total derivative instruments		332
Carrying amount \| Interest rate swaps designated as a hedge \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,581
Total derivative instruments	7,008	19,649
Carrying amount \| Commodity contracts for regulated operations
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,721	194
Total derivative instruments	1,348	614
Carrying amount \| Cross-currency swap designated as a net investment hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,958
Carrying amount \| Cross-currency swap designated as a net investment hedge \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	50,258	84,218
Carrying amount \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Preferred shares, Series C	13,348	13,698
Fair value
Fair Value of Financial Instruments [Line Items]
Long-term investments carried at fair value	1,848,456	1,839,212
Development loans and other receivables	33,286	31,088
Total derivative instruments	20,622	52,107
Total financial assets	1,902,364	1,922,407
Long-term debt	6,543,933	5,140,059
Notes payable to related party	25,808	30,493
Convertible debentures	519	623
Total derivative instruments	120,245	110,410
Total financial liabilities	6,705,085	5,297,150
Fair value \| Energy contracts \| Designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	15,362	51,525
Total derivative instruments	60,462	5,597
Fair value \| Energy contracts \| Not designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,169
Fair value \| Energy contracts \| Not designated as a hedge \| Cash flow hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments		388
Total derivative instruments		332
Fair value \| Interest rate swaps designated as a hedge \| Designated as a hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,581
Total derivative instruments	7,008	19,649
Fair value \| Commodity contracts for regulated operations
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,721	194
Total derivative instruments	1,348	614
Fair value \| Cross-currency swap designated as a net investment hedge
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	1,958
Fair value \| Cross-currency swap designated as a net investment hedge \| Designated as a hedge \| Net Investment Hedging
Fair Value of Financial Instruments [Line Items]
Total derivative instruments	50,258	84,218
Fair value \| Series C Preferred Stock
Fair Value of Financial Instruments [Line Items]
Preferred shares, Series C	$ 14,580	$ 15,565

Fair Value of Financial Instruments [Line Items]

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Long-term Investments, Fair Value

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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.

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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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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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Fair value of financial and nonfinancial obligations.

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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.

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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.

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The amount for notes payable (written promise to pay), due to related parties.

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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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