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Quarterly Operating Results (Unaudited) - Impact of fair value accounting on annuities (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
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Dec. 31, 2020 | Sep. 30, 2020 | Jun. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Sep. 30, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2020 | Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract] |  |  |  |  |  |  |  |  |  |
Impact of unlocking, changes in the fair value of derivatives, and changes in the stock market and interest rates on the accounting for FIAs | $ (48) | $ (43) | $ (59) | $ (38) | $ 24 | $ (27) | $ (33) | $ (11) | $ (188) | $ (47)

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- Definition Impact of unlocking, changes in the fair value of derivatives, and changes in the stock market and interest rates on the accounting for FIAs + References No definition available. + Details
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