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Investments - Scheduled maturities of available for sale fixed maturities (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2018 USD ($)
Fair Value Percent, Fiscal Year Maturity [Abstract] |
Average life of ABS | 4 years 6 months
Average life of MBS | 4 years 6 months
Fixed maturities |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |
One year or less | $ 1,212
After one year through five years | 8,150
After five years through ten years | 13,372
After ten years | 4,749
Fixed maturities amortized cost, Subtotal | 27,483
ABS (average life of approximately 4-1/2 years) | 9,249
MBS (average life of approximately 4-1/2 years) | 3,321
Amortized Cost | 40,053
Fair Value, Fiscal Year Maturity [Abstract] |
One year or less | 1,223
After one year through five years | 8,184
After five years through ten years | 13,211
After ten years | 4,687
Fixed maturities fair value, Subtotal | 27,305
ABS (average life of approximately 4-1/2 years) | 9,307
MBS (average life of approximately 4-1/2 years) | 3,632
Fair Value | $ 40,244
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 | 33.00%
After ten years | 12.00%
Fixed maturities fair value, Subtotal, Percent | 68.00%
ABS (average life of approximately 4-1/2 years) | 23.00%
MBS (average life of approximately 4-1/2 years) | 9.00%
Fair value, Total, Percent | 100.00%

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