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Segment Information (Narrative) (Details) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2023 USD ($) | Sep. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Sep. 30, 2022 USD ($) | Jun. 30, 2022 USD ($) | Mar. 31, 2022 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2023 USD ($) Segment | Dec. 31, 2023 USD ($) segment | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Segment Reporting [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of segments |  |  |  |  |  |  |  |  |  | 6 | 6 |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | $ 687,584 |  |  |  | $ 663,072 |  |  |  | $ 687,584 | $ 687,584 | $ 687,584 | $ 687,584 | $ 663,072 |
Total revenues | 19,028 | $ 15,866 | $ 16,623 | $ 15,388 | 15,608 | $ 22,283 | $ 15,474 | $ 15,405 | 66,905 |  |  |  | 68,770 | $ 68,696
Number of Reportable Segments |  |  |  |  |  |  |  |  |  | 6 | 6 |  |  |
Retirement and Income Solutions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | 218,587 |  |  |  | 216,370 |  |  |  | 218,587 | $ 218,587 | $ 218,587 | $ 218,587 | $ 216,370 |
Net investment income from equity method investments |  |  |  |  |  |  |  |  |  |  |  | 1.00% | 6.00% | 26.00%
Asia |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | 157,206 |  |  |  | 148,305 |  |  |  | 157,206 | 157,206 | 157,206 | $ 157,206 | $ 148,305 |
Net investment income from equity method investments |  |  |  |  |  |  |  |  |  |  |  | 4.00% | 12.00% | 30.00%
Latin America |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | 69,177 |  |  |  | 63,687 |  |  |  | 69,177 | 69,177 | 69,177 | $ 69,177 | $ 63,687 |
Net investment income from equity method investments |  |  |  |  |  |  |  |  |  |  |  | 1.00% | 3.00% | 7.00%
MetLife Holdings |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | 148,524 |  |  |  | 148,749 |  |  |  | 148,524 | 148,524 | 148,524 | $ 148,524 | $ 148,749 |
Net investment income from equity method investments |  |  |  |  |  |  |  |  |  |  |  | 2.00% | 6.00% | 26.00%
Group Benefits |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | 36,715 |  |  |  | 35,849 |  |  |  | 36,715 | 36,715 | 36,715 | $ 36,715 | $ 35,849 |
Net investment income from equity method investments |  |  |  |  |  |  |  |  |  |  |  | 0.00% | 1.00% | 5.00%
One.U.S.Customer | Retirement and Income Solutions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total revenues |  |  |  |  |  |  |  |  | 8,100 |  |  |  |  |
Japan |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total assets (1),(2) | $ 132,200 |  |  |  | $ 125,100 |  |  |  | $ 132,200 | $ 132,200 | $ 132,200 | $ 132,200 | $ 125,100 |
Assets, Total | Geographic Concentration Risk | Japan |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  | 19.00% | 19.00% |
Revenue Benchmark | Customer Concentration Risk | One.U.S.Customer | Retirement and Income Solutions |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  | 14.00% |  |
Customer Concentration Risk |  |  |  |  |  |  |  |  |  |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Benchmark Description |  |  |  |  |  |  |  |  |  |  |  |  | 10 | 10

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