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v3.21.2

Business Segments (Narrative) (Detail) $ in Millions |  | 3 Months Ended | 6 Months Ended
--- | --- | --- | ---
Jul. 01, 2021 USD ($) | Sep. 30, 2021 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2020 USD ($) | Jun. 30, 2021 USD ($) segments | Jun. 30, 2020 USD ($)
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Number of operating segments | segments |  |  |  |  |  | 3 |
Revenue from customers | [1] |  |  | $ 29 | $ 39 | $ 64 | $ 82
International And Structured Finance Insurance [Member] | Termination Of Insurance Policy [Member] | Subsequent Event [Member] |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Reduction of financial obligations of total insured gross par outstanding |  | $ 441 |  |  |  |  |
International And Structured Finance Insurance [Member] | Termination Of Insurance Policy [Member] | Subsequent Event [Member] | Scenario, Forecast [Member] |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |
Revenue from customers |  |  | $ 19 |  |  |  |
[1] | Represents the sum of third-party financial guarantee net premiums earned, net investment income, insurance-related fees and reimbursements and other fees.

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- Definition Amount of increase (decrease) in accrued obligations to policy and contract holders for long-duration insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (b),(c) -URI http://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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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 http://asc.fasb.org/extlink&oid=120311839&loc=d3e8672-108599 + Details
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