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Property, Plant and Equipment (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021
Property, Plant and Equipment [Line Items] |  |
Total gross property, plant and equipment | $ 8,374,790 | $ 7,856,573
Less accumulated depreciation and depletion | (1,576,842) | (1,407,397)
Property, plant and equipment of variable interest entities, net | 6,797,948 | 6,449,176
Corporate, Non-Segment |  |
Property, Plant and Equipment [Line Items] |  |
Property, Plant and Equipment | 5,685 | 5,694
Construction in progress, gross | 13,690 | 8,460
Total gross property, plant and equipment | 19,375 | 14,154
Less accumulated depreciation and depletion | (1,773) | (1,544)
Property, plant and equipment of variable interest entities, net | $ 17,602 | $ 12,610
Weighted Average | Corporate, Non-Segment |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 11 years | 10 years
Minimum | Corporate, Non-Segment |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 4 years |
Maximum | Corporate, Non-Segment |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 24 years |
Production, Gas | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 45 years | 40 years
Production, Gas | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 24 years |
Production, Gas | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 47 years |
Gas transmission | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 58 years | 58 years
Gas transmission | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 32 years |
Gas transmission | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 72 years |
Gas distribution | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 57 years | 53 years
Gas distribution | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 48 years |
Gas distribution | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 60 years |
Cushion gas - depreciable | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life |  | 28 years
Gas, Storage | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 41 years | 38 years
Gas, Storage | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 36 years |
Gas, Storage | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 48 years |
General | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 23 years | 21 years
General | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 3 years |
General | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 25 years |
Electric Utilities |  |
Property, Plant and Equipment [Line Items] |  |
Total plant in service before construction work in progress | $ 4,190,734 | $ 3,991,095
Construction work in progress | 152,953 | 181,451
Property, Plant and Equipment | 4,343,687 | 4,172,546
Less accumulated depreciation and depletion | (1,104,056) | (1,016,738)
Property, plant and equipment of variable interest entities, net | $ 3,239,631 | 3,155,808
Depreciation, depletion and amortization, remaining amortization period | 8 years |
Electric Utilities | Production, Electric |  |
Property, Plant and Equipment [Line Items] |  |
Production, processing and storage | $ 1,482,081 | $ 1,452,055
Electric Utilities | Production, Electric | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 41 years | 41 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 | 46 years |
Electric Utilities | Electric transmission |  |
Property, Plant and Equipment [Line Items] |  |
Transmission | $ 632,872 | $ 546,126
Electric Utilities | Electric transmission | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 48 years | 49 years
Electric Utilities | Electric transmission | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 40 years |
Electric Utilities | Electric transmission | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 51 years |
Electric Utilities | Electric distribution |  |
Property, Plant and Equipment [Line Items] |  |
Distribution | $ 1,082,535 | $ 1,000,619
Electric Utilities | Electric distribution | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 47 years | 47 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 | 50 years |
Electric Utilities | Integrated Generation |  |
Property, Plant and Equipment [Line Items] |  |
Plant acquisition adjustment | $ 713,519 | $ 720,490
Electric Utilities | Integrated Generation | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 31 years | 30 years
Electric Utilities | Integrated Generation | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 19 years |
Electric Utilities | Integrated Generation | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 38 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 | $ 274,857 | $ 266,935
Electric Utilities | General | Weighted Average |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 27 years | 28 years
Electric Utilities | General | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Weighted average useful life | 24 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 | $ 3,959,687 | $ 3,632,013
Construction in progress, gross | 52,041 | 37,860
Total gross property, plant and equipment | 4,011,728 | 3,669,873
Less accumulated depreciation and depletion | (471,013) | (389,115)
Property, plant and equipment of variable interest entities, net | 3,540,715 | 3,280,758
Gas Utilities | Production, Gas |  |
Property, Plant and Equipment [Line Items] |  |
Production, processing and storage | 17,843 | 14,841
Gas Utilities | Gas transmission |  |
Property, Plant and Equipment [Line Items] |  |
Transmission | 695,345 | 645,550
Gas Utilities | Gas distribution |  |
Property, Plant and Equipment [Line Items] |  |
Distribution | 2,620,174 | 2,394,352
Gas Utilities | Cushion gas - depreciable |  |
Property, Plant and Equipment [Line Items] |  |
Production, processing and storage |  | 3,539
Gas Utilities | Cushion gas - not depreciable |  |
Property, Plant and Equipment [Line Items] |  |
Production, processing and storage | 63,137 | 42,478
Gas Utilities | Gas, Storage |  |
Property, Plant and Equipment [Line Items] |  |
Production, processing and storage | 65,781 | 56,289
Gas Utilities | General |  |
Property, Plant and Equipment [Line Items] |  |
General | $ 497,407 | $ 474,964

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