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General (Effects of Adoption ASU 2018-12, Segment Results) (Details) - USD ($) $ in Millions | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2022 | Dec. 31, 2022 | Dec. 31, 2020
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Net incurred claims and benefits (1) | $ 1,646 | $ 1,472 |  |  |
Core income (loss) before income tax | 406 | 366 |  |  |
Income tax (expense) benefit on core income (loss) | (81) | (68) |  |  |
Core income (loss) | 325 | 298 |  |  |
Claim and claim adjustment expenses | 22,409 |  | $ 22,120 | [1] |
Future policy benefits | 13,976 | 16,002 | 13,480 | [1] | $ 19,132
Life & Group | Operating Segments |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Net incurred claims and benefits (1) | 311 | 304 |  |  |
Core income (loss) before income tax | (12) | (7) |  |  |
Income tax (expense) benefit on core income (loss) | 9 | 12 |  |  |
Core income (loss) | (3) | 5 |  |  |
Claim and claim adjustment expenses | 704 |  | 695 |  |
Future policy benefits | $ 13,976 |  | 13,480 |  |
Prior to Adoption |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Claim and claim adjustment expenses |  |  | 25,099 |  |
Future policy benefits |  |  | 10,151 |  | $ 13,318
Prior to Adoption | Life & Group | Operating Segments |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Net incurred claims and benefits (1) |  | 281 |  |  |
Core income (loss) before income tax |  | 16 |  |  |
Income tax (expense) benefit on core income (loss) |  | 7 |  |  |
Core income (loss) |  | 23 |  |  |
Claim and claim adjustment expenses |  |  | 3,674 |  |
Future policy benefits |  |  | 10,151 |  |
Effect of Adoption |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Claim and claim adjustment expenses |  |  | (2,979) |  |
Future policy benefits |  |  | 3,329 |  |
Effect of Adoption | Life & Group | Operating Segments |  |  |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |  |  |
Net incurred claims and benefits (1) |  | 23 |  |  |
Core income (loss) before income tax |  | (23) |  |  |
Income tax (expense) benefit on core income (loss) |  | 5 |  |  |
Core income (loss) |  | $ (18) |  |  |
Claim and claim adjustment expenses |  |  | (2,979) |  |
Future policy benefits |  |  | $ 3,329 |  |
[1] | As of January 1, 2023, the Company adopted ASU 2018-12 using the modified retrospective method applied as of the transition date of January 1, 2021. Prior period amounts in the financial statements have been adjusted to reflect application of the new guidance. See Note A to the Condensed Consolidated Financial Statements for additional information.

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