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BENEFIT PLANS (Tables) | 12 Months Ended
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Dec. 31, 2023
Schedule of Net Funded Status | Information with respect to the Company's benefit plans' assets and obligations as of December 31 was as follows:
|  | Pension Benefits |  | Other
|  | Japan |  | U.S. |  | Postretirement Benefits
(In millions) |  | 2023 | 2022 |  | 2023 | 2022 |  | 2023 | 2022
Projected benefit obligation: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefit obligation, beginning of year |  |  | $ | 327 |  |  |  | $ | 432 |  |  |  |  | $ | 843 |  |  |  | $ | 1,186 |  |  |  |  | $ | 32 |  |  |  | $ | 36 |  |
Service cost |  |  | 14 |  |  |  | 19 |  |  |  |  | 7 |  |  |  | 26 |  |  |  |  | 0 |  |  |  | 0 |  |
Interest cost |  |  | 9 |  |  |  | 5 |  |  |  |  | 41 |  |  |  | 34 |  |  |  |  | 1 |  |  |  | 1 |  |
Actuarial (gain) loss |  |  | 7 |  |  |  | (61) |  |  |  |  | 37 |  |  |  | (374) |  |  |  |  | (4) |  |  |  | 0 |  |
Benefits and expenses paid |  |  | (13) |  |  |  | (13) |  |  |  |  | (58) |  |  |  | (29) |  |  |  |  | (4) |  |  |  | (5) |  |
Curtailment (gain) loss |  |  | 0 |  |  |  | 0 |  |  |  |  | (106) |  |  |  | 0 |  |  |  |  | 0 |  |  |  | 0 |  |
Effect of foreign exchange rate changes |  |  | (20) |  |  |  | (55) |  |  |  |  | 0 |  |  |  | 0 |  |  |  |  | 0 |  |  |  | 0 |  |
Benefit obligation, end of year |  |  | 324 |  |  |  | 327 |  |  |  |  | 764 |  |  |  | 843 |  |  |  |  | 25 |  |  |  | 32 |  |
Plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fair value of plan assets, beginning of year |  |  | 335 |  |  |  | 415 |  |  |  |  | 659 |  |  |  | 885 |  |  |  |  | 0 |  |  |  | 0 |  |
Actual return on plan assets |  |  | 17 |  |  |  | (46) |  |  |  |  | 39 |  |  |  | (205) |  |  |  |  | 0 |  |  |  | 0 |  |
Employer contributions |  |  | 27 |  |  |  | 34 |  |  |  |  | 8 |  |  |  | 8 |  |  |  |  | 4 |  |  |  | 5 |  |
Benefits and expenses paid |  |  | (13) |  |  |  | (13) |  |  |  |  | (58) |  |  |  | (29) |  |  |  |  | (4) |  |  |  | (5) |  |
Effect of foreign exchange rate changes |  |  | (22) |  |  |  | (55) |  |  |  |  | 0 |  |  |  | 0 |  |  |  |  | 0 |  |  |  | 0 |  |
Fair value of plan assets, end of year |  |  | 344 |  |  |  | 335 |  |  |  |  | 648 |  |  |  | 659 |  |  |  |  | 0 |  |  |  | 0 |  |
Funded status of the plans(1) |  |  | $ | 20 |  |  |  | $ | 8 |  |  |  |  | $ | (116) |  |  |  | $ | (184) |  |  |  |  | $ | (25) |  |  |  | $ | (32) |  |
Amounts recognized in accumulated other comprehensive income: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net actuarial (gain) loss |  |  | $ | 30 |  |  |  | $ | 35 |  |  |  |  | $ | (13) |  |  |  | $ | 10 |  |  |  |  | $ | 2 |  |  |  | $ | 8 |  |
Prior service (credit) cost |  |  | 0 |  |  |  | 0 |  |  |  |  | (2) |  |  |  | (2) |  |  |  |  | 0 |  |  |  | 0 |  |
Total included in accumulated other comprehensive income |  |  | $ | 30 |  |  |  | $ | 35 |  |  |  |  | $ | (15) |  |  |  | $ | 8 |  |  |  |  | $ | 2 |  |  |  | $ | 8 |  |
Accumulated benefit obligation |  |  | $ | 213 |  |  |  | $ | 215 |  |  |  |  | $ | 764 |  |  |  | $ | 741 |  |  |  |  | N/A |  |  | N/A |
(1) Underfunded amounts are recognized in other liabilities in the consolidated balance sheets and overfunded amounts are recognized in other assets in the consolidated balance sheets
Information for Pension Plans with Accumulated Benefit Obligation in Excess of Plan Assets | Information for Pension Plans with an Accumulated Benefit Obligation in Excess of Plan Assets
|  | Pension Benefits
|  | Japan |  |  |  | U.S.
(In millions) |  | 2023 |  | 2022 |  |  |  | 2023 |  | 2022 |
Accumulated benefit obligation |  |  | $ | 213 |  |  |  |  | $ | 215 |  |  |  |  |  | $ | 764 |  |  |  |  | $ | 741 |  |
Fair value of plan assets |  |  | 344 |  |  |  |  | 335 |  |  |  |  |  | 648 |  |  |  |  | 659 |  |
Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets | Information for Pension Plans with a Projected Benefit Obligation in Excess of Plan Assets
|  | Pension Benefits
|  | Japan (1) |  |  |  | U.S.(2)
(In millions) |  | 2023 |  | 2022 |  |  |  | 2023 |  | 2022 |
Projected benefit obligation |  |  | $ | 324 |  |  |  |  | $ | 327 |  |  |  |  |  | $ | 764 |  |  |  |  | $ | 843 |  |
Fair value of plan assets |  |  | 344 |  |  |  |  | 335 |  |  |  |  |  | 648 |  |  |  |  | 659 |  |
(1) The net amount of projected benefit obligation and plan assets for the overfunded Japan pension plan was $20 and $8 at December 31, 2023 and 2022, respectively, and was classified as other assets on the statement of financial position. (2) The net amount of projected benefit obligation and plan assets for the underfunded (including unfunded) U.S. pension plan was $116 and $184 at December 31, 2023 and 2022, respectively, and was classified as liabilities on the statement of financial position.
Schedule of Assumptions Used |
| Pension Benefits |  | Other
| Japan |  |  | U.S. |  |  | Postretirement Benefits
| 2023 |  | 2022 |  | 2021 |  |  | 2023 |  | 2022 |  | 2021 |  |  | 2023 |  | 2022 |  | 2021 |
Weighted-average actuarial assumptions: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate - net periodic benefit cost | 1.95 | % |  | .94 | % |  | .75 | % |  |  | 5.24 | % | (1) | 2.94 | % |  | 2.68 | % |  |  | 5.28 | % |  | 2.94 | % |  | 2.68 | % |
Discount rate - benefit obligations | 1.84 |  |  | 1.95 |  |  | .94 |  |  |  | 5.04 |  |  | 5.28 |  |  | 2.94 |  |  |  | 5.04 |  |  | 5.28 |  |  | 2.94 |  |
Expected long-term return on plan assets | 2.00 |  |  | 2.00 |  |  | 2.00 |  |  |  | 4.75 |  |  | 5.50 |  |  | 5.75 |  |  |  | N/A |  | N/A |  | N/A |
Rate of compensation increase | N/A |  | N/A |  | N/A |  |  | 4.00 |  |  | 4.00 |  |  | 4.00 |  |  |  | N/A |  | N/A |  | N/A |
Health care cost trend rates | N/A |  | N/A |  | N/A |  |  | N/A |  | N/A |  | N/A |  |  | 6.80 |  | (2) | 6.50 |  | (2) | 5.80 |  | (2)
(1) An interim valuation was required due to the U.S. pension plan curtailment. The rate shown is the rate used on the interim valuation date of June 12, 2023. (2) For the years 2023, 2022 and 2021, the health care cost trend rates are expected to trend down to 3.7% in 50 years, 3.7% in 51 years, and 3.7% in 52 years, respectively.
Schedule of Net Benefit Costs | Total net periodic benefit cost includes the following components:
|  | Pension Benefits |  | Other
|  |  | Japan |  |  | U.S. |  | Postretirement Benefits
(In millions) |  | 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021
Service cost |  |  | $ | 14 |  |  |  |  | $ | 19 |  |  |  |  | $ | 23 |  |  |  |  | $ | 7 |  |  |  |  | $ | 26 |  |  |  |  | $ | 28 |  |  |  |  | $ | 0 |  |  |  |  | $ | 0 |  |  |  |  | $ | 0 |  |
Interest cost |  |  | 9 |  |  |  |  | 5 |  |  |  |  | 6 |  |  |  |  | 41 |  |  |  |  | 34 |  |  |  |  | 32 |  |  |  |  | 1 |  |  |  |  | 1 |  |  |  |  | 1 |  |
Expected return on plan assets |  |  | (7) |  |  |  |  | (8) |  |  |  |  | (8) |  |  |  |  | (34) |  |  |  |  | (42) |  |  |  |  | (41) |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |
Amortization of net actuarial loss |  |  | 0 |  |  |  |  | 1 |  |  |  |  | 2 |  |  |  |  | (2) |  |  |  |  | 21 |  |  |  |  | 30 |  |  |  |  | 2 |  |  |  |  | 2 |  |  |  |  | 3 |  |
Curtailment (gain) loss |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | (49) |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |
Net periodic (benefit) cost |  |  | $ | 16 |  |  |  |  | $ | 17 |  |  |  |  | $ | 23 |  |  |  |  | $ | (37) |  |  |  |  | $ | 39 |  |  |  |  | $ | 49 |  |  |  |  | $ | 3 |  |  |  |  | $ | 3 |  |  |  |  | $ | 4 |  |
Schedule of Amounts Recognized in Other Comprehensive Income (Loss) | The following table summarizes the amounts recognized in other comprehensive loss (income) for the years ended December 31:
|  | Pension Benefits |  | Other
|  | Japan |  | U.S. |  | Postretirement Benefits
(In millions) |  | 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021 |  | 2023 |  | 2022 |  | 2021
Net actuarial loss (gain) |  |  | $ | (5) |  |  |  |  | $ | (14) |  |  |  |  | $ | (22) |  |  |  |  | $ | 31 |  |  |  |  | $ | (127) |  |  |  |  | $ | (90) |  |  |  |  | $ | (4) |  |  |  |  | $ | 0 |  |  |  |  | $ | (2) |  |
Amortization of net actuarial loss |  |  | 0 |  |  |  |  | (1) |  |  |  |  | (2) |  |  |  |  | 2 |  |  |  |  | (21) |  |  |  |  | (30) |  |  |  |  | (2) |  |  |  |  | (2) |  |  |  |  | (3) |  |
Amortization of prior service cost |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 1 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |
Curtailment (gain) loss |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | (57) |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 0 |  |
Total |  |  | $ | (5) |  |  |  |  | $ | (15) |  |  |  |  | $ | (23) |  |  |  |  | $ | (24) |  |  |  |  | $ | (148) |  |  |  |  | $ | (120) |  |  |  |  | $ | (6) |  |  |  |  | $ | (2) |  |  |  |  | $ | (5) |  |
Schedule of Expected Benefit Payments | The following table provides expected benefit payments, which reflect expected future service, as appropriate.
|  | Pension Benefits |  | Other
(In millions) |  | Japan | U.S. |  | Postretirement Benefits
2024 |  |  | $ | 10 |  |  |  | $ | 34 |  |  |  |  | $ | 4 |  |
2025 |  |  | 16 |  |  |  | 35 |  |  |  |  | 4 |  |
2026 |  |  | 12 |  |  |  | 37 |  |  |  |  | 4 |  |
2027 |  |  | 12 |  |  |  | 44 |  |  |  |  | 3 |  |
2028 |  |  | 13 |  |  |  | 44 |  |  |  |  | 2 |  |
2029-2033 |  |  | 74 |  |  |  | 234 |  |  |  |  | 4 |  |
Schedule of Allocation of Plan Assets | Asset allocation targets as of December 31, 2023 were as follows:
|  | Japan Pension |  | U.S. Pension
Domestic equities |  |  | 6 | % |  |  |  | 0 | % |
International equities |  |  | 11 |  |  |  |  | 0 |  |
Fixed income securities |  |  | 63 |  |  |  |  | 100 |  |
Other |  |  | 20 |  |  |  |  | 0 |  |
Total |  |  | 100 | % |  |  |  | 100 | % |
Plan Assets |
Fair Value, Assets Measured on Recurring Basis | The following tables present the fair value of Aflac Japan's pension plan assets that are measured at fair value on a recurring basis as of December 31.
| 2023
(In millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Total Fair Value
Japan pension plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Japanese equity securities |  | $ | 0 |  |  |  |  | $ | 21 |  |  |  |  | $ | 0 |  |  |  |  | $ | 21 |  |
International equity securities |  | 0 |  |  |  |  | 38 |  |  |  |  | 0 |  |  |  |  | 38 |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Japanese bonds |  | 0 |  |  |  |  | 22 |  |  |  |  | 0 |  |  |  |  | 22 |  |
International bonds |  | 0 |  |  |  |  | 194 |  |  |  |  | 0 |  |  |  |  | 194 |  |
Insurance contracts |  | 0 |  |  |  |  | 26 |  |  |  |  | 0 |  |  |  |  | 26 |  |
Alternative investments |  | 0 |  |  |  |  | 0 |  |  |  |  | 16 |  |  |  |  | 16 |  |
Cash and cash equivalents |  | 27 |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  |  | 27 |  |
Total |  | $ | 27 |  |  |  |  | $ | 301 |  |  |  |  | $ | 16 |  |  |  |  | $ | 344 |  |
| 2022
(In millions) | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Total Fair Value
Japan pension plan assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Japanese equity securities |  | $ | 0 |  |  |  |  | $ | 20 |  |  |  |  | $ | 0 |  |  |  |  | $ | 20 |  |
International equity securities |  | 0 |  |  |  |  | 57 |  |  |  |  | 0 |  |  |  |  | 57 |  |
Fixed income securities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Japanese bonds |  | 0 |  |  |  |  | 20 |  |  |  |  | 0 |  |  |  |  | 20 |  |
International bonds |  | 0 |  |  |  |  | 210 |  |  |  |  | 0 |  |  |  |  | 210 |  |
Insurance contracts |  | 0 |  |  |  |  | 28 |  |  |  |  | 0 |  |  |  |  | 28 |  |
Total |  | $ | 0 |  |  |  |  | $ | 335 |  |  |  |  | $ | 0 |  |  |  |  | $ | 335 |  |
The following table presents the fair value of Aflac U.S.'s pension plan assets that are measured at fair value on a recurring basis as of December 31. All of these assets are classified as Level 1 in the fair value hierarchy.
(In millions) | 2023 |  | 2022
U.S. pension plan assets: |  |  |  |  |  |  |
Mutual funds: |  |  |  |  |  |  |
Fixed income bond funds |  | 648 |  |  |  |  | $ | 641 |  |
Cash and cash equivalents |  | 0 |  |  |  |  | 18 |  |
Total |  | $ | 648 |  |  |  |  | $ | 659 |  |
Aflac Japan | Plan Assets |
Schedule of Changes in Fair Value of Plan Assets | The following table presents the changes in fair value of Aflac Japan' pension plan assets that are classified as Level 3.
(In millions) | Alternative Investments
Balance at December 31, 2022 |  | $ | 0 |  |
Actual return on plan assets: |  |  |
Relating to assets still held at the reporting date |  | 0 |  |
Relating to assets sold during the period |  | 0 |  |
Purchases, sales and settlements |  | 16 |  |
Transfers in and/or out of Level 3 |  | 0 |  |
Balance at December 31, 2023 |  | $ | 16 |  |

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- Definition Tabular disclosure of the net gain (loss) and net prior service cost or credit recognized in other comprehensive income (loss) for the period for pension plans and/or other employee benefit plans, and reclassification adjustments of other comprehensive income (loss) for the period, as those amounts, including amortization of the net transition asset or obligation, are recognized as components of net periodic benefit cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 715 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (i) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480506/715-20-50-1 + Details
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