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General (Pre-Transition LFPB to Adjusted Opening Balance) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | --- | ---
Present value of future net premiums |  |  |
Effect of change in cash flow assumptions | $ 0 | $ 0 |
Reclassification of reserves for policyholders on claim to Future policy benefits |  |  |
Present value of future net premiums |  |  |
Effect of change in cash flow assumptions |  |  | $ 2,844
De-recognition of shadow reserves |  |  |
Present value of future net premiums |  |  |
Effect of change in cash flow assumptions |  |  | (3,293)
Re-measurement using an upper-medium grade fixed income instrument yield discount rate |  |  |
Present value of future net premiums |  |  |
Effect of change in cash flow assumptions |  |  | 6,255
Other adjustments |  |  |
Present value of future net premiums |  |  |
Effect of change in cash flow assumptions |  |  | $ 8

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