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Fair Value of Financial Instruments (Company's Assets And Liabilities Measured At Fair Value On Recurring Basis) (Detail) - Fair Value Measurements Recurring [Member] - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | $ 1,769 |  | $ 2,094
Fair value financial liabilities measured on recurring basis | 73 |  | 134
Money Market Securities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 181 |  | 34
Medium-term Notes [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 35 |  | 40
Equity investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 117 | [1] | 155
Cash and Cash Equivalents [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 84 |  | 104
Fixed Maturities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 1,356 |  | 1,739
Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 481 |  | 712
Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 102 |  | 123
Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 10 |  | 18
Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 451 |  | 497
Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 111 |  | 149
Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 41 |  | 34
Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 7 |  | 14
Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 101 |  | 146
Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 52 |  | 46
Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 10
Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 10
Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 1
Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 1
Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 28 |  | 35
Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 3 |  | 3
Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 2
Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 1 |  | 1
Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis |  |  | 1
Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 6 |  | 14
Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 31 |  | 78
Fair Value Inputs Level 1 [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 797 |  | 885
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Money Market Securities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 181 |  | 34
Fair Value Inputs Level 1 [Member] | Medium-term Notes [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Equity investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 48 |  | 39
Fair Value Inputs Level 1 [Member] | Cash and Cash Equivalents [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 84 |  | 104
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 481 |  | 705
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 481 |  | 705
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 3 |  | 3
Fair Value Inputs Level 1 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis |  |  | 0
Fair Value Inputs Level 1 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 1 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 866 |  | 1,063
Fair value financial liabilities measured on recurring basis | 1 |  | 2
Fair Value Inputs Level 2 [Member] | Money Market Securities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Medium-term Notes [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Equity investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 7 |  | 8
Fair Value Inputs Level 2 [Member] | Cash and Cash Equivalents [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 859 |  | 1,033
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 7
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 102 |  | 123
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 10 |  | 18
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 435 |  | 496
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 111 |  | 149
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 41 |  | 34
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 7 |  | 14
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 101 |  | 146
Fair Value Inputs Level 2 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 52 |  | 46
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 10
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 10
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 1
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 1
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 2 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 1 |  | 1
Fair Value Inputs Level 2 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis |  |  | 1
Fair Value Inputs Level 2 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 2 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 96 |  | 146
Fair value financial liabilities measured on recurring basis | 72 |  | 132
Fair Value Inputs Level 3 [Member] | Money Market Securities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Medium-term Notes [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 35 |  | 40
Fair Value Inputs Level 3 [Member] | Equity investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 52 |  | 108
Fair Value Inputs Level 3 [Member] | Cash and Cash Equivalents [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 16 |  | 1
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | U.S. Treasury And Government Agency [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | State and municipal bonds [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Foreign Government Debt [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Corporate Obligations [Member] | Other Fixed Maturity Investments [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 16 | [2] | 1
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Fixed Maturities [Member] | Other Asset Backed [Member] | Asset-backed [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Residential Mortgage Backed Non Agency [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Commercial Mortgage Backed Securities [Member] | Mortgage-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Collateralized Debt Obligations [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Other Asset Backed [Member] | Asset-backed [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Loans Receivable and Other Instruments At Fair Value [Member] | Variable Interest Entity, Primary Beneficiary [Member] | Residential Loans Receivable [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 28 |  | 35
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Cash and Cash Equivalents [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Assets Of Consolidated V I Es [Member] | Other [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial assets measured on recurring basis |  |  | 2
Fair Value Inputs Level 3 [Member] | Other Liabilities [Member] | Credit Derivatives [Member] | Insured Derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 0 |  | 0
Fair Value Inputs Level 3 [Member] | Other Liabilities [Member] | Interest rate derivatives [Member] | Non-insured interest rate derivatives [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis |  |  | 0
Fair Value Inputs Level 3 [Member] | Liabilities Of Consolidated Vies [Member] | Currency Derivatives [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | 6 |  | 14
Fair Value Inputs Level 3 [Member] | Liabilities Of Consolidated Vies [Member] | Variable Interest Entity Notes [Member] | Variable Interest Entity, Primary Beneficiary [Member] |  |  |
Accounts Notes And Loans Receivable [Line Items] |  |  |
Fair value financial liabilities measured on recurring basis | $ 31 |  | $ 78
[1] | Includes $10 million of an exchange-traded bond fund that seeks to track the investment results of an index composed of U.S. dollar-denominated, high yield corporate bonds. The fund is measured at fair value by applying the net asset value per share practical expedient, and is not required to be classified in the fair value hierarchy.
[2] | Includes loans carried at fair value of $15 million.

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