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Schedule I - Investments (Detail) $ in Millions | Dec. 31, 2023 USD ($)
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Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | $ 2,064
Fair Value | 1,931
Amount at which shown in the balance sheet | 1,931
Other Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 3
Fair Value | 3
Amount at which shown in the balance sheet | 3
Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 67
Fair Value | 57
Amount at which shown in the balance sheet | 57
Loans Receivable [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 47
Fair Value | 35
Amount at which shown in the balance sheet | 35
Long-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 1,175
Fair Value | 1,043
Amount at which shown in the balance sheet | 1,043
Long-Term Available-For-Sale [Member] | U.S. Treasury And Government Agency [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 214
Fair Value | 198
Amount at which shown in the balance sheet | 198
Long-Term Available-For-Sale [Member] | US States And Political Subdivisions [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 128
Fair Value | 123
Amount at which shown in the balance sheet | 123
Long-Term Available-For-Sale [Member] | Foreign Governments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 13
Fair Value | 11
Amount at which shown in the balance sheet | 11
Long-Term Available-For-Sale [Member] | Corporate Obligations [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 504
Fair Value | 417
Amount at which shown in the balance sheet | 417
Short-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 513
Fair Value | 514
Amount at which shown in the balance sheet | 514
AFS Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 1,688
Fair Value | 1,557
Amount at which shown in the balance sheet | 1,557
Investments At Fair Value [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 373
Fair Value | 371
Amount at which shown in the balance sheet | 371
Investments At Fair Value [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 20
Fair Value | 22
Amount at which shown in the balance sheet | 22
Mortgage-backed [Member] | Long-Term Available-For-Sale [Member] | Residential Mortgage backed Agency [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 149
Fair Value | 135
Amount at which shown in the balance sheet | 135
Mortgage-backed [Member] | Long-Term Available-For-Sale [Member] | Residential Mortgage-Backed Non Agency [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 31
Fair Value | 26
Amount at which shown in the balance sheet | 26
Mortgage-backed [Member] | Long-Term Available-For-Sale [Member] | Commercial Mortgage-Backed [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 14
Fair Value | 13
Amount at which shown in the balance sheet | 13
Asset-backed [Member] | Long-Term Available-For-Sale [Member] | Collateralized Debt Obligations [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 96
Fair Value | 95
Amount at which shown in the balance sheet | 95
Asset-backed [Member] | Long-Term Available-For-Sale [Member] | Other Asset-Backed [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 26
Fair Value | 25
Amount at which shown in the balance sheet | $ 25

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