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Schedule I- Investments (Detail) $ in Millions | Dec. 31, 2015 USD ($)
--- | ---
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | $ 6,371
Fair Value | 6,350
Amount at which shown in the balance sheet | 6,350
Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 4,235
Fair Value | 4,625
Amount at which shown in the balance sheet | 4,913
Other Aggregated 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
Loans Receivable [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 685
Fair Value | 1,292
Amount at which shown in the balance sheet | 1,292
Long-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 5,308
Fair Value | 5,266
Amount at which shown in the balance sheet | 5,266
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 | 838
Fair Value | 866
Amount at which shown in the balance sheet | 866
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 | 1,629
Fair Value | 1,680
Amount at which shown in the balance sheet | 1,680
Long-Term Available-For-Sale [Member] | Foreign Governments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 149
Fair Value | 150
Amount at which shown in the balance sheet | 150
Long-Term Available-For-Sale [Member] | Corporate Obligations [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 1,304
Fair Value | 1,221
Amount at which shown in the balance sheet | 1,221
Short-Term Available-For-Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 840
Fair Value | 841
Amount at which shown in the balance sheet | 841
Equity Available For Sale [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 12
Fair Value | 13
Amount at which shown in the balance sheet | 13
AFS Investments [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 6,160
Fair Value | 6,120
Amount at which shown in the balance sheet | 6,120
Investments At Fair Value [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 208
Fair Value | 227
Amount at which shown in the balance sheet | 227
Investments At Fair Value [Member] | Assets Of Consolidated VIEs [Member] |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |
Cost | 861
Fair Value | 932
Amount at which shown in the balance sheet | 932
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 | 2,689
Fair Value | 2,401
Amount at which shown in the balance sheet | 2,689
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 | 995
Fair Value | 993
Amount at which shown in the balance sheet | 993
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 | 54
Fair Value | 50
Amount at which shown in the balance sheet | 50
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 | 29
Fair Value | 29
Amount at which shown in the balance sheet | 29
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 | 50
Fair Value | 33
Amount at which shown in the balance sheet | 33
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 | 260
Fair Value | 244
Amount at which shown in the balance sheet | $ 244

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