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Business Developments And Risks And Uncertainties (Narrative) (Detail) $ in Millions |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jul. 01, 2023 USD ($) | Jan. 01, 2023 USD ($) | Mar. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) Segments | Jun. 26, 2023 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Number of operating segments | Segments |  |  |  | 3 |
Correction of error income (loss) from discontinued operations, net of tax |  |  | $ 18 |  |
Noncontrolling Interest [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Correction of error income (loss) from discontinued operations, net of tax |  |  | $ 8 |  |
Puerto Rico Electric Power Authority [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Outstanding bonds |  |  |  | $ 808 |
Maximum [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Liabilities Subject to Compromise, Provision for Expected and Allowed Claims |  |  |  |  | $ 7,600
Minimum [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Liabilities Subject to Compromise, Provision for Expected and Allowed Claims |  |  |  |  | $ 2,400
Puerto Rico [Member] | National Public Finance Guarantee Corporation [Member] |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Claims payments | $ 119 | $ 18 |  |  |

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