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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of CLOs and Other ABS | 4 years |
Average life of MBS | 4 years 6 months |
Securities With Non-Credit Other Than Temporary Impairment Charges [Member] |  |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax | $ (1) | $ (4)
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | 1,764 |
After one year through five years | 10,613 |
After five years through ten years | 13,513 |
After ten years | 3,539 |
Fixed maturities amortized cost, Subtotal | 29,429 |
Collateralized loan obligations and other ABS (average life of approximately 4 years) | 11,299 |
MBS (average life of approximately 4-1/2 years) | 3,796 |
Amortized Cost | 44,524 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 1,793 |
After one year through five years | 11,044 |
After five years through ten years | 14,419 |
After ten years | 3,754 |
Fixed maturities fair value, Subtotal | 31,010 |
Collateralized loan obligations and other ABS (average life of approximately 4 years) | 11,408 |
MBS (average life of approximately 4-1/2 years) | 4,087 |
Fair Value | $ 46,505 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 4.00% |
After one year through five years | 24.00% |
After five years through ten years | 31.00% |
After ten years | 8.00% |
Fixed maturities fair value, Subtotal, Percent | 67.00% |
Collateralized loan obligations and other ABS (average life of approximately 4 years) | 24.00% |
MBS (average life of approximately 4-1/2 years) | 9.00% |
Fair value, Total, Percent | 100.00% |

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