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Schedule I (Details) - USD ($) $ in Millions | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Other Investments | $ 6,062 | $ 5,277
Cost or Amortized Cost | 106,179 |
Fair Value | 109,511 |
Amount at Which Shown in the Balance Sheet | 109,087 |
All Related Party [Member] |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Other Investments | 147 |
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 | 82,580 |
Fair Value | 85,488 |
Amount at Which Shown in the Balance Sheet | 85,488 |
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 | 3,188 |
Fair Value | 3,283 |
Amount at Which Shown in the Balance Sheet | 3,283 |
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 | 22,670 |
Fair Value | 23,707 |
Amount at Which Shown in the Balance Sheet | 23,707 |
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 | 30,689 |
Fair Value | 31,791 |
Amount at Which Shown in the Balance Sheet | 31,791 |
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 | 18,712 |
Fair Value | 19,192 |
Amount at Which Shown in the Balance Sheet | 19,192 |
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 | 7,321 |
Fair Value | 7,515 |
Amount at Which Shown in the Balance Sheet | 7,515 |
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 | 12,581 |
Fair Value | 13,005 |
Amount at Which Shown in the Balance Sheet | 12,581 |
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 | 1,318 |
Fair Value | 1,347 |
Amount at Which Shown in the Balance Sheet | 1,318 |
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 | 1,423 |
Fair Value | 1,485 |
Amount at Which Shown in the Balance Sheet | 1,423 |
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 | 2,349 |
Fair Value | 2,468 |
Amount at Which Shown in the Balance Sheet | 2,349 |
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 | 2,331 |
Fair Value | 2,396 |
Amount at Which Shown in the Balance Sheet | 2,331 |
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 | 5,160 |
Fair Value | 5,309 |
Amount at Which Shown in the Balance Sheet | 5,160 |
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 | 812 |
Fair Value | 812 |
Amount at Which Shown in the Balance Sheet | 812 |
Short-term investments |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 4,291 |
Fair Value | 4,291 |
Amount at Which Shown in the Balance Sheet | 4,291 |
Other investments |  |
SEC Schedule, 12-15, Insurance Companies, Summary of Investments, Other than Investments in Related Parties [Line Items] |  |
Cost or Amortized Cost | 5,915 |
Fair Value | 5,915 |
Amount at Which Shown in the Balance Sheet | $ 5,915 |

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