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Schedule I - Investments (Detail) $ in Millions | Dec. 31, 2022 USD ($)
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Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | $ 2,938
Fair Value | 2,676
Amount at which shown in the balance sheet | 2,676
Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 176
Fair Value | 125
Amount at which shown in the balance sheet | 125
Loans Receivable [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 113
Fair Value | 78
Amount at which shown in the balance sheet | 78
Long-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,044
Fair Value | 1,812
Amount at which shown in the balance sheet | 1,812
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 | 427
Fair Value | 394
Amount at which shown in the balance sheet | 394
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 | 173
Fair Value | 164
Amount at which shown in the balance sheet | 164
Long-Term Available-For-Sale [Member] | Foreign Governments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 18
Fair Value | 15
Amount at which shown in the balance sheet | 15
Long-Term Available-For-Sale [Member] | Corporate Obligations [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 862
Fair Value | 715
Amount at which shown in the balance sheet | 715
Short-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 119
Fair Value | 119
Amount at which shown in the balance sheet | 119
AFS Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,163
Fair Value | 1,931
Amount at which shown in the balance sheet | 1,931
Investments At Fair Value [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 775
Fair Value | 745
Amount at which shown in the balance sheet | 745
Investments At Fair Value [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 63
Fair Value | 47
Amount at which shown in the balance sheet | 47
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 | 217
Fair Value | 195
Amount at which shown in the balance sheet | 195
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 | 96
Fair Value | 88
Amount at which shown in the balance sheet | 88
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 | 24
Fair Value | 23
Amount at which shown in the balance sheet | 23
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 | 117
Fair Value | 112
Amount at which shown in the balance sheet | 112
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 | 110
Fair Value | 106
Amount at which shown in the balance sheet | $ 106

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