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Investments - Narrative (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 USD ($) security | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Investment [Line Items] |  |  |
Percentage (based on amount of unrealized loss) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 74.00% |  |
Percentage (based on fair value) of available for sale fixed maturities that are in an unrealized loss position and rated investment grade | 93.00% |  |
Other than temporary impairment charges | $ 19 | $ 19 | $ 73
Average life of CLOs and Other ABS | 4 years |  |
Average life of MBS | 4 years 6 months |  |
Residential MBS |  |  |
Investment [Line Items] |  |  |
Non-credit related portion of other-than-temporary impairment charges taken for securities still owned | $ 118 | 140 |
Fixed maturities, Gross Unrealized, Losses | (5) | (9) |
Other than temporary impairment charges | 1 | 6 | 1
Collateralized loan obligations |  |  |
Investment [Line Items] |  |  |
Fixed maturities, Gross Unrealized, Losses | (37) | (73) |
Other than temporary impairment charges | 17 |  |
Corporate bond securities |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges | 11 |  |
Securities with non-credit other-than-temporary impairment charges |  |  |
Investment [Line Items] |  |  |
Gross Unrealized, Gains | 114 | 119 |
Gross Unrealized, Losses | (1) | (4) |
Fixed maturities |  |  |
Investment [Line Items] |  |  |
Fixed maturities, Gross Unrealized, Losses | $ (88) | (603) |
Number of available for sale securities in an unrealized loss position | security | 649 |  |
Other than temporary impairment charges | $ 29 | 26 | 20
Available-for-sale Securities, Gross Realized Gains | 35 | 22 | 43
Available-for-sale Securities, Gross Realized Losses | (19) | (14) | (20)
Fixed maturities excluding residential MBS |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges |  | 20 | 19
Other investments |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges |  |  | 4
Equity securities |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges | $ 0 | $ 0 | 64
Available-for-sale Securities, Gross Realized Gains |  |  | 87
Available-for-sale Securities, Gross Realized Losses |  |  | (17)
Equity securities | Available-for-sale securities |  |  |
Investment [Line Items] |  |  |
Other than temporary impairment charges |  |  | $ 64

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