Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment	$ 7,856,573	$ 7,305,530
Less accumulated depreciation and depletion	(1,407,397)	(1,285,816)
Property, plant and equipment of variable interest entities, net	6,449,176	6,019,714
Corporate, Non-Segment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment	5,694	5,692
Construction in progress, gross	8,460	16,402
Property, plant and equipment	14,154	22,094
Less accumulated depreciation and depletion	(1,544)	(1,144)
Property, plant and equipment of variable interest entities, net	$ 12,610	$ 20,950
Weighted Average \| Corporate, Non-Segment
Property, Plant and Equipment [Line Items]
Weighted average useful life	10 years	10 years
Minimum \| Corporate, Non-Segment
Property, Plant and Equipment [Line Items]
Weighted average useful life	10 years	10 years
Maximum \| Corporate, Non-Segment
Property, Plant and Equipment [Line Items]
Weighted average useful life	22 years	22 years
Electric Utilities
Property, Plant and Equipment [Line Items]
Total plant in service before construction work in progress	$ 3,991,095	$ 3,875,557
Construction work in progress	181,451	95,266
Property, plant and equipment	4,172,546	3,970,823
Less accumulated depreciation and depletion	(1,016,738)	(960,993)
Property, plant and equipment of variable interest entities, net	$ 3,155,808	3,009,830
Depreciation, depletion and amortization, remaining amortization period	9 years
Electric Utilities \| Production, Electric
Property, Plant and Equipment [Line Items]
Production, processing and storage	$ 1,452,055	$ 1,417,951
Electric Utilities \| Production, Electric \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	41 years	40 years
Electric Utilities \| Production, Electric \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	32 years
Electric Utilities \| Production, Electric \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	45 years
Electric Utilities \| Electric transmission
Property, Plant and Equipment [Line Items]
Transmission	$ 546,126	$ 517,794
Electric Utilities \| Electric transmission \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	49 years	49 years
Electric Utilities \| Electric transmission \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	43 years
Electric Utilities \| Electric transmission \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	50 years
Electric Utilities \| Electric distribution
Property, Plant and Equipment [Line Items]
Distribution	$ 1,000,619	$ 959,453
Electric Utilities \| Electric distribution \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	47 years	46 years
Electric Utilities \| Electric distribution \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	45 years
Electric Utilities \| Electric distribution \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	49 years
Electric Utilities \| Integrated Generation
Property, Plant and Equipment [Line Items]
Plant acquisition adjustment	$ 720,490	$ 716,479
Electric Utilities \| Integrated Generation \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	30 years	31 years
Electric Utilities \| Integrated Generation \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	2 years
Electric Utilities \| Integrated Generation \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	59 years
Electric Utilities \| Plant acquisition adjustment
Property, Plant and Equipment [Line Items]
Plant acquisition adjustment	$ 4,870	$ 4,870
Electric Utilities \| Plant acquisition adjustment \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	32 years	32 years
Electric Utilities \| Plant acquisition adjustment \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	32 years
Electric Utilities \| Plant acquisition adjustment \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	32 years
Electric Utilities \| General
Property, Plant and Equipment [Line Items]
General	$ 266,935	$ 259,010
Electric Utilities \| General \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	28 years	28 years
Electric Utilities \| General \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	25 years
Electric Utilities \| General \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	31 years
Gas Utilities
Property, Plant and Equipment [Line Items]
Total plant in service before construction work in progress	$ 3,632,013	$ 3,245,384
Construction work in progress	37,860	67,229
Property, plant and equipment	3,669,873	3,312,613
Less accumulated depreciation and depletion	(389,115)	(323,679)
Property, plant and equipment of variable interest entities, net	3,280,758	2,988,934
Gas Utilities \| Production, Gas
Property, Plant and Equipment [Line Items]
Production, processing and storage	$ 14,841	$ 15,603
Gas Utilities \| Production, Gas \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	40 years	40 years
Gas Utilities \| Production, Gas \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	24 years
Gas Utilities \| Production, Gas \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	46 years
Gas Utilities \| Gas transmission
Property, Plant and Equipment [Line Items]
Transmission	$ 645,550	$ 578,278
Gas Utilities \| Gas transmission \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	58 years	54 years
Gas Utilities \| Gas transmission \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	22 years
Gas Utilities \| Gas transmission \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	71 years
Gas Utilities \| Gas distribution
Property, Plant and Equipment [Line Items]
Distribution	$ 2,394,352	$ 2,115,082
Gas Utilities \| Gas distribution \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	53 years	53 years
Gas Utilities \| Gas distribution \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	45 years
Gas Utilities \| Gas distribution \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	59 years
Gas Utilities \| Cushion gas - depreciable
Property, Plant and Equipment [Line Items]
Production, processing and storage	$ 3,539	$ 3,539
Gas Utilities \| Cushion gas - depreciable \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	28 years	28 years
Gas Utilities \| Cushion gas - depreciable \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	28 years
Gas Utilities \| Cushion gas - depreciable \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	28 years
Gas Utilities \| Cushion gas - not depreciable
Property, Plant and Equipment [Line Items]
Production, processing and storage	$ 42,478	$ 39,184
Gas Utilities \| Gas, Storage
Property, Plant and Equipment [Line Items]
Production, processing and storage	$ 56,289	$ 55,481
Gas Utilities \| Gas, Storage \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	38 years	38 years
Gas Utilities \| Gas, Storage \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	27 years
Gas Utilities \| Gas, Storage \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	52 years
Gas Utilities \| General
Property, Plant and Equipment [Line Items]
General	$ 474,964	$ 438,217
Gas Utilities \| General \| Weighted Average
Property, Plant and Equipment [Line Items]
Weighted average useful life	21 years	19 years
Gas Utilities \| General \| Minimum
Property, Plant and Equipment [Line Items]
Weighted average useful life	3 years
Gas Utilities \| General \| Maximum
Property, Plant and Equipment [Line Items]
Weighted average useful life	23 years

The depreciation, depletion or amortization period remaining on an asset.

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Property Plant Equipment excluding Construction in Progress

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Public Utilities, Property, Plant and Equipment Excluding Construction in Progress

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Amount of acquisition adjustments included in property, plant and equipment (PPE) for utilities.

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Period end amount of construction work in progress in public utility.

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Period end amount of property, plant and equipment (PPE) related to utility distribution.

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Period end amount of property, plant and equipment (PPE) related to generation or processing owned by public utility.

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Period end book value of other property, plant and equipment (PPE) owned (but not classified elsewhere) by the public utility.

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Period end amount of property, plant and equipment (PPE) related to utility transmission owned by public utility.

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