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Schedule I- Investments (Detail) $ in Millions | Dec. 31, 2019 USD ($)
--- | ---
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | $ 3,343
Fair Value | 3,462
Amount at which shown in the balance sheet | 3,462
Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 1,125
Fair Value | 1,111
Amount at which shown in the balance sheet | 1,109
Loans Receivable [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 135
Fair Value | 136
Amount at which shown in the balance sheet | 136
Long-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,714
Fair Value | 2,829
Amount at which shown in the balance sheet | 2,829
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 | 640
Fair Value | 685
Amount at which shown in the balance sheet | 685
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 | 178
Fair Value | 200
Amount at which shown in the balance sheet | 200
Long-Term Available-For-Sale [Member] | Foreign Governments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2
Fair Value | 2
Amount at which shown in the balance sheet | 2
Long-Term Available-For-Sale [Member] | Corporate Obligations [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 1,078
Fair Value | 1,129
Amount at which shown in the balance sheet | 1,129
Short-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 270
Fair Value | 270
Amount at which shown in the balance sheet | 270
AFS Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 2,984
Fair Value | 3,099
Amount at which shown in the balance sheet | 3,099
Investments At Fair Value [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 359
Fair Value | 363
Amount at which shown in the balance sheet | 363
Investments At Fair Value [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 100
Fair Value | 83
Amount at which shown in the balance sheet | 83
Held-To-Maturity [Member] | Corporate Obligations [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 890
Fair Value | 892
Amount at which shown in the balance sheet | 890
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 | 317
Fair Value | 320
Amount at which shown in the balance sheet | 320
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 | 23
Fair Value | 19
Amount at which shown in the balance sheet | 19
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 | 20
Fair Value | 20
Amount at which shown in the balance sheet | 20
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 | 139
Fair Value | 137
Amount at which shown in the balance sheet | 137
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 | 317
Fair Value | 317
Amount at which shown in the balance sheet | $ 317

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