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Summary of Significant Accounting Policies - Estimated Retirement Costs Collected from Customers (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
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Regulated Asset Liability [Line Items] |  |
Regulatory liability for utility plant retirement costs | $ 834 | $ 857
Utility Plant Retirement Costs [Member] |  |
Regulated Asset Liability [Line Items] |  |
Regulatory liability for utility plant retirement costs | $ 448 | $ 417

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- Definition The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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