RETIREMENT BENEFITS - Contributions (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |
|---|---|---|---|
Dec. 31, 2024 |
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| U.S. plans | Pension plans | |||
| Defined Benefit Plan, Expected Future Employer Contributions [Abstract] | |||
| Company contributions (reimbursements) | $ 63 | $ 59 | |
| U.S. plans | Postretirement benefit plans | |||
| Defined Benefit Plan, Expected Future Employer Contributions [Abstract] | |||
| Company contributions (reimbursements) | 5 | 8 | |
| Non-U.S. plans | Pension plans | |||
| Defined Benefit Plan, Expected Future Employer Contributions [Abstract] | |||
| Company contributions (reimbursements) | 93 | 763 | |
| Discretionary contribution | $ 600 | ||
| Non-U.S. plans | Postretirement benefit plans | |||
| Defined Benefit Plan, Expected Future Employer Contributions [Abstract] | |||
| Company contributions (reimbursements) | $ 11 | $ 9 | |