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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 4 years 6 months |
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 | $ (4) | $ (4)
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | 1,310 |
After one year through five years | 8,521 |
After five years through ten years | 14,235 |
After ten years | 4,609 |
Fixed maturities amortized cost, Subtotal | 28,675 |
ABS (average life of approximately 4.5 years) | 9,781 |
MBS (average life of approximately 4.5 years) | 3,381 |
Amortized Cost | 41,837 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 1,318 |
After one year through five years | 8,554 |
After five years through ten years | 14,044 |
After ten years | 4,606 |
Fixed maturities fair value, Subtotal | 28,522 |
ABS (average life of approximately 4.5 years) | 9,811 |
MBS (average life of approximately 4.5 years) | 3,664 |
Fair Value | $ 41,997 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 3.00% |
After one year through five years | 20.00% |
After five years through ten years | 34.00% |
After ten years | 11.00% |
Fixed maturities fair value, Subtotal, Percent | 68.00% |
ABS (average life of approximately 4.5 years) | 23.00% |
MBS (average life of approximately 4.5 years) | 9.00% |
Fair value, Total, Percent | 100.00% |

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