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Fair Value of Financial Instruments (Quantitative Information Regarding The Significant Unobservable Inputs For Certain Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Detail) - USD ($)
$ in Millions

Dec. 31, 2024

Dec. 31, 2023

Discounted Cash Flow [Member] | Equity Investments [Member] | EBITDA Multiples Discount Rate Hard Asset Values Type Certificate Values [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Fair Value, assets

^[1]

$ 108

Discounted Cash Flow [Member] | Loans Carried at Fair Value [Member] | Discount Rate [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Fair Value, assets

^[2]

$ 15

Discounted Cash Flow Type Certificate [Member] | Equity Investments [Member] | Discount Rate EBITDA Multiple EBITDA Royalty Share [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Fair Value, assets

^[2]

52

Variable Interest Entity Primary Beneficiary [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Fair value, liabilities

78

Variable Interest Entity Primary Beneficiary [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Fair Value, assets

$ 28

$ 35

Variable Interest Entity Primary Beneficiary [Member] | Minimum [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

74.00%

Variable Interest Entity Primary Beneficiary [Member] | Minimum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

27.00%

27.00%

Variable Interest Entity Primary Beneficiary [Member] | Maximum [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

74.00%

Variable Interest Entity Primary Beneficiary [Member] | Maximum [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

27.00%

27.00%

Variable Interest Entity Primary Beneficiary [Member] | Weighted Average [Member] | Variable Interest Entity Notes [Member] | Impact Of Financial Guarantee [Member] | Market Prices Of VIE Assets Adjusted For Financial Guarantees Provided Or Market Prices Of Similar Liabilities [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

^[3]

74.00%

Variable Interest Entity Primary Beneficiary [Member] | Weighted Average [Member] | Loans Receivable and Other Instruments at Fair Value [Member] | Impact Of Financial Guarantee [Member] | Market Prices of Similar Liabilities Adjusted for Financial Guarantees Provided to VIE Obligations [Member]

Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]

Range percentage

^[4]

27.00%

27.00%

[1]	Range for EBITDA multiples, discount rate, weightings, hard asset values and type certificate values are not meaningful.
[2]	Ranges for discount rate, EBITDA multiple and EBITDA royalty share are not meaningful.
[3]	Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value.S
[4]	Weighted average represents the total MBIA guarantees as a percentage of total instrument fair value.

X

- Definition

This element represents the fair value measurement range percentage of the Company's assets and liabilities measured at fair value.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

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