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Contracts Accounted for as Insurance - Net Expected Loss to be Expensed Insurance Contracts (Details) $ in Millions | Sep. 30, 2025 USD ($)
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Insurance [Abstract] |
2025 (October 1 - December 31) | $ 3
2026 | 14
2027 | 17
2028 | 20
2029 | 18
2030-2034 | 81
2035-2039 | 37
2040-2044 | 19
2045-2049 | 25
2050-2054 | 20
After 2054 | 3
Net expected loss to be expensed (present value) | 257
Future accretion | 27
Total expected future loss and LAE | $ 284

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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed Beyond Thirty-First Fiscal Year from Balance Sheet Date + References No definition available. + Details
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Period Type: | instant

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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed During Fourth Quarter Following Balance Sheet Date + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts, Future Expected, Net Loss to be Expensed in First Full Fiscal Year + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 16 and within 20 Years from Balance Sheet Date + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 21 and Within 25 Years from Balance Sheet Date + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 26 and Within 30 Years from Balance Sheet Date + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than Four and Within 9 Years from Balance Sheet Date + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Financial Guarantee Insurance Contracts Future Expected Net Loss to be Expensed More than 10 and within 15 Years from Balance Sheet Date + References No definition available. + Details
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- Definition For financial guarantee insurance contracts, the amount of net loss expected to be expensed within the fourth full fiscal year following the date of the latest balance sheet presented in the financial statements. + References No definition available. + Details
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Balance Type: | debit
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- Definition For financial guaranty insurance contracts, the amount of net loss expected to be expensed within the second full fiscal year following the date of the latest balance sheet presented in the financial statements. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Financial Guarantee Insurance Contracts, Future Expected, Net Loss to be Expensed in Third Full Fiscal Year + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts, Net Loss to be Expensed, Present Value + References No definition available. + Details
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- Definition Financial Guarantee Insurance Contracts, Net Loss to be Expensed, Undiscounted + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
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- Definition Schedule of Insured Financial Obligations with Credit Deterioration, Reductions of Gross Claim Liability, Net of Reinsurance Recoverable, Discount (Accretion) + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- References No definition available. + Details
Name: | us-gaap_InsuranceAbstract
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