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Schedule I (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Other Investments | $ 7,945 | $ 6,062
Cost or Amortized Cost | 113,023 |
Fair Value | 119,407 |
Amount at Which Shown in the Balance Sheet | 118,550 |
All Related Party [Member] |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Other Investments | 119 |
Fixed maturities available for sale |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 85,168 |
Fair Value | 90,699 |
Amount at Which Shown in the Balance Sheet | 90,699 |
Fixed maturities available for sale | U.S. Treasury and agency |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 2,471 |
Fair Value | 2,670 |
Amount at Which Shown in the Balance Sheet | 2,670 |
Fixed maturities available for sale | Foreign |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 24,588 |
Fair Value | 26,354 |
Amount at Which Shown in the Balance Sheet | 26,354 |
Fixed maturities available for sale | Corporate securities |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 34,081 |
Fair Value | 36,331 |
Amount at Which Shown in the Balance Sheet | 36,331 |
Fixed maturities available for sale | Mortgage-backed securities |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 17,456 |
Fair Value | 18,470 |
Amount at Which Shown in the Balance Sheet | 18,470 |
Fixed maturities available for sale | States, municipalities, and political subdivisions |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 6,572 |
Fair Value | 6,874 |
Amount at Which Shown in the Balance Sheet | 6,874 |
Fixed maturities held to maturity |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 11,653 |
Fair Value | 12,510 |
Amount at Which Shown in the Balance Sheet | 11,653 |
Fixed maturities held to maturity | U.S. Treasury and agency |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 1,392 |
Fair Value | 1,452 |
Amount at Which Shown in the Balance Sheet | 1,392 |
Fixed maturities held to maturity | Foreign |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 1,288 |
Fair Value | 1,405 |
Amount at Which Shown in the Balance Sheet | 1,288 |
Fixed maturities held to maturity | Corporate securities |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 2,150 |
Fair Value | 2,438 |
Amount at Which Shown in the Balance Sheet | 2,150 |
Fixed maturities held to maturity | Mortgage-backed securities |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 1,999 |
Fair Value | 2,146 |
Amount at Which Shown in the Balance Sheet | 1,999 |
Fixed maturities held to maturity | States, municipalities, and political subdivisions |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 4,824 |
Fair Value | 5,069 |
Amount at Which Shown in the Balance Sheet | 4,824 |
Industrial, miscellaneous, and all others |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 4,027 |
Fair Value | 4,027 |
Amount at Which Shown in the Balance Sheet | 4,027 |
Short-term investments |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 4,349 |
Fair Value | 4,345 |
Amount at Which Shown in the Balance Sheet | 4,345 |
Other investments |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 7,826 |
Fair Value | 7,826 |
Amount at Which Shown in the Balance Sheet | $ 7,826 |

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