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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, 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 | $ 793
After one year through five years | 7,314
After five years through ten years | 13,345
After ten years | 4,731
Fixed maturities amortized cost, Subtotal | 26,183
ABS (average life of approximately 4-1/2 years) | 8,546
MBS (average life of approximately 4-1/2 years) | 3,654
Amortized Cost | 38,383
Fair Value, Fiscal Year Maturity [Abstract] |
One year or less | 804
After one year through five years | 7,431
After five years through ten years | 13,425
After ten years | 4,799
Fixed maturities fair value, Subtotal | 26,459
ABS (average life of approximately 4-1/2 years) | 8,663
MBS (average life of approximately 4-1/2 years) | 4,003
Fair Value | $ 39,125
Fair Value Percent, Fiscal Year Maturity [Abstract] |
One year or less | 2.00%
After one year through five years | 19.00%
After five years through ten years | 35.00%
After ten years | 12.00%
Fixed maturities fair value, Subtotal, Percent | 68.00%
ABS (average life of approximately 4-1/2 years) | 22.00%
MBS (average life of approximately 4-1/2 years) | 10.00%
Fair value, Total, Percent | 100.00%

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- Definition Amount after adjustments of available-for-sale debt securities at cost, maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Adjustments include, but are not limited to, accretion, amortization, collection of cash, previous other-than-temporary impairments (OTTI) recognized in earnings less cumulative-effect adjustments, and fair value hedge accounting adjustments. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27198-111563 + Details
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