v3.26.1
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
Mar. 31, 2026
Dec. 31, 2025
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis $ 1,751 $ 1,779
Fair value financial liabilities measured on recurring basis 79 83
Money Market Securities [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 65 109
Medium-term Notes [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial liabilities measured on recurring basis 43 46
Equity investments [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 96 [1] 97 [2]
Cash and Cash Equivalents [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 70 69
Fixed Maturities [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 1,484 1,468
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 438 473
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 99 100
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 5 5
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 473 433
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 111 117
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 22 21
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 16 18
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 82 49
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 238 252
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 34 34
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 2 2
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 12 12
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 24 25
Fair Value Inputs Level 1 [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 621 700
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 65 109
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 46 [1] 47 [2]
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 70 69
Fair Value Inputs Level 1 [Member] | Fixed Maturities [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 438 473
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 438 473
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] | 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 2 2
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 1,033 984
Fair value financial liabilities measured on recurring basis 0 0
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 6 [1] 7 [2]
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 1,027 977
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 0
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 99 100
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 5 5
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 454 415
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 111 117
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 22 21
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 16 18
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 82 49
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 238 252
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] | 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 87 85
Fair value financial liabilities measured on recurring basis 79 83
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 43 46
Fair Value Inputs Level 3 [Member] | Equity investments [Member]    
Accounts Notes And Loans Receivable [Line Items]    
Fair value financial assets measured on recurring basis 34 [1] 33 [2]
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 19 18
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 19 [3] 18 [4]
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] | 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 34 34
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] | 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 12 12
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 $ 24 $ 25
[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 $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.
[3] Includes loans carried at fair value of $18 million.
[4] Includes loans carried at fair value of $17 million.