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Investments - Scheduled maturities of available for sale fixed maturities (Details) - USD ($) $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2021 | Dec. 31, 2020
Fair Value, Fiscal Year Maturity [Abstract] |  |
Fair Value | $ 10,427 | $ 9,084
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
Average life of ABS | 3 years |
Average life of MBS | 3 years |
Fixed maturities |  |
Amortized Cost Basis, Fiscal Year Maturity [Abstract] |  |
One year or less | $ 1,182 |
After one year through five years | 2,571 |
After five years through ten years | 901 |
After ten years | 284 |
Fixed maturities amortized cost, Subtotal | 4,938 |
Collateralized loan obligations and other ABS (average life of approximately 3 years) | 4,450 |
MBS (average life of approximately 3 years) | 814 |
Amortized Cost | 10,202 |
Fair Value, Fiscal Year Maturity [Abstract] |  |
One year or less | 1,194 |
After one year through five years | 2,662 |
After five years through ten years | 939 |
After ten years | 292 |
Fixed maturities fair value, Subtotal | 5,087 |
Collateralized loan obligations and other ABS (average life of approximately 3 years) | 4,473 |
MBS (average life of approximately 3 years) | 867 |
Fair Value | $ 10,427 | $ 9,084
Fair Value Percent, Fiscal Year Maturity [Abstract] |  |
One year or less | 11.00% |
After one year through five years | 26.00% |
After five years through ten years | 9.00% |
After ten years | 3.00% |
Fixed maturities fair value, Subtotal, Percent | 49.00% |
Collateralized loan obligations and other ABS (average life of approximately 3 years) | 43.00% |
MBS (average life of approximately 3 years) | 8.00% |
Fair value, Total, Percent | 100.00% |

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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27198-111563 + Details
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- Definition Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27198-111563 + Details
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