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Investments - Scheduled maturities of available for sale fixed maturities (Details) $ in Millions | 6 Months Ended
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Jun. 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 | $ 994
After one year through five years | 7,703
After five years through ten years | 13,386
After ten years | 4,828
Fixed maturities amortized cost, Subtotal | 26,911
ABS (average life of approximately 4-1/2 years) | 8,849
MBS (average life of approximately 4-1/2 years) | 3,484
Amortized Cost | 39,244
Fair Value, Fiscal Year Maturity [Abstract] |
One year or less | 1,003
After one year through five years | 7,764
After five years through ten years | 13,285
After ten years | 4,841
Fixed maturities fair value, Subtotal | 26,893
ABS (average life of approximately 4-1/2 years) | 8,935
MBS (average life of approximately 4-1/2 years) | 3,820
Fair Value | $ 39,648
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) | 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 of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562 + Details
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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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