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Business Developments And Risks And Uncertainties (Narrative) (Detail) $ in Millions |  | 3 Months Ended
--- | --- | ---
Jan. 01, 2023 USD ($) | Mar. 31, 2023 USD ($) segments
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 |  | 926
Puerto Rico [Member] |  |
Business Acquisition [Line Items] |  |
Outstanding bonds |  | $ 1,000
Puerto Rico [Member] | National Public Finance Guarantee Corporation [Member] |  |
Business Acquisition [Line Items] |  |
Claims payments | $ 18 |

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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 18 -URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599 + Details
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