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Schedule I- Investments (Detail) $ in Millions | Dec. 31, 2021 USD ($)
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Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | $ 2,639
Fair Value | 2,793
Amount at which shown in the balance sheet | 2,793
Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 176
Fair Value | 137
Amount at which shown in the balance sheet | 137
Loans Receivable [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 108
Fair Value | 77
Amount at which shown in the balance sheet | 77
Long-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,018
Fair Value | 2,159
Amount at which shown in the balance sheet | 2,159
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 | 515
Fair Value | 566
Amount at which shown in the balance sheet | 566
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 | 140
Fair Value | 167
Amount at which shown in the balance sheet | 167
Long-Term Available-For-Sale [Member] | Foreign Governments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 11
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 | 881
Fair Value | 930
Amount at which shown in the balance sheet | 930
Short-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 298
Fair Value | 298
Amount at which shown in the balance sheet | 298
AFS Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,316
Fair Value | 2,457
Amount at which shown in the balance sheet | 2,457
Investments At Fair Value [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 323
Fair Value | 336
Amount at which shown in the balance sheet | 336
Investments At Fair Value [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 68
Fair Value | 60
Amount at which shown in the balance sheet | 60
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 | 190
Fair Value | 192
Amount at which shown in the balance sheet | 192
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 | 80
Fair Value | 92
Amount at which shown in the balance sheet | 92
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 | 10
Fair Value | 10
Amount at which shown in the balance sheet | 10
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 | 101
Fair Value | 101
Amount at which shown in the balance sheet | 101
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 | 90
Fair Value | 90
Amount at which shown in the balance sheet | $ 90

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