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Pension Plans and Other Postretirement Benefit Plans - Additional Information (Details) - USD ($) | 9 Months Ended
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Sep. 30, 2022 | Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items] |  |
Payment for pension benefits | $ 42,000,000 | $ 42,000,000
Percentage of service related net periodic benefit costs capitalized to utility property | 40.00% |
Percentage of service related net periodic benefit costs recorded to operating expenses | 60.00% |
Percentage of non-service related net periodic benefit costs capitalized to regulatory assets | 40.00% |
Percentage of non-service related net periodic benefit costs recorded to other expense | 60.00% |
Pension Plans, Defined Benefit [Member] |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Expected contributions to pension plan | $ 0 |

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- Definition Percentage of non-service related net periodic benefit costs capitalized to regulatory assets. + References No definition available. + Details
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- Definition Percentage of non-service related net periodic benefit costs recorded to other expense. + References No definition available. + Details
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- Definition Percentage of service related net periodic benefit costs capitalized to utility property. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Amount of contribution expected to be received by defined benefit plan from employer in remainder of current fiscal year. Excludes contribution previously paid by employer in current fiscal year. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4587-114921 + Details
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- Definition Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (g) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3536-108585 + Details
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