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Investments - Scheduled maturities of available for sale fixed maturities (Details) $ in Millions | 3 Months Ended
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Mar. 31, 2020 USD ($)
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 4 years 6 months |
Average life of MBS | 3 years 6 months |
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 2,018 | [1]
After one year through five years | 10,563 | [1]
After five years through ten years | 14,450 | [1]
After ten years | 3,551 | [1]
Fixed maturities amortized cost, Subtotal | 30,582 | [1]
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years) | 11,494 | [1]
MBS (average life of approximately 3-1/2 years) | 3,964 | [1]
Amortized Cost | 46,040 | [1]
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 2,027 |
After one year through five years | 10,710 |
After five years through ten years | 14,722 |
After ten years | 3,741 |
Fixed maturities fair value, Subtotal | 31,200 |
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years) | 10,896 |
MBS (average life of approximately 3-1/2 years) | 4,038 |
Fair Value | $ 46,134 |
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 4.00% |
After one year through five years | 23.00% |
After five years through ten years | 32.00% |
After ten years | 8.00% |
Fixed maturities fair value, Subtotal, Percent | 67.00% |
Collateralized loan obligations and other ABS (average life of approximately 4-1/2 years) | 24.00% |
MBS (average life of approximately 3-1/2 years) | 9.00% |
Fair value, Total, Percent | 100.00% |
[1] | Amortized cost, net of allowance for expected credit losses.

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