| **RETIREMENT BENEFITS - Roll Forward of Plan Assets and Funded Status (Details) - USD ($) $ in Millions** | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------|-----------------|
||
| **Change in plan assets**                                                                                 |            |   |
| Plan assets at beginning of fiscal year                                                                   | $ 7,653         | $ 9,924 |
| Actual return on plan assets                                                                              | 1,041           | (1,567) |
| Acquisitions                                                                                              | 749             | 0 |
| Employer contributions                                                                                    | 29              | 11 |
| Benefits paid                                                                                             | (591)           | (648) |
| Expenses paid                                                                                             | (34)            | (26) |
| Currency translation adjustment                                                                           | 12              | (32) |
| Divestiture                                                                                               | 0               | (10) |
| Other                                                                                                     | 1               | 1 |
| Plan assets at end of fiscal year                                                                         | 8,860           | 7,653 |
| Funded status                                                                                             | 66              | (69) |
| Pension                                                                                                   |            |   |
| **Change in plan assets**                                                                                 |            |   |
| Plan assets at beginning of fiscal year                                                                   | 7,411           | 9,604 |
| Actual return on plan assets                                                                              | 1,004           | (1,516) |
| Acquisitions                                                                                              | 749             | 0 |
| Employer contributions                                                                                    | 20              | 16 |
| Benefits paid                                                                                             | (568)           | (626) |
| Expenses paid                                                                                             | (34)            | (26) |
| Currency translation adjustment                                                                           | 12              | (32) |
| Divestiture                                                                                               | 0               | (10) |
| Other                                                                                                     | 1               | 1 |
| Plan assets at end of fiscal year                                                                         | 8,595           | 7,411 |
| Funded status                                                                                             | 32              | (83) |
| Other Benefits                                                                                            |            |   |
| **Change in plan assets**                                                                                 |            |   |
| Plan assets at beginning of fiscal year                                                                   | 242             | 320 |
| Actual return on plan assets                                                                              | 37              | (51) |
| Acquisitions                                                                                              | 0               | 0 |
| Employer contributions                                                                                    | 9               | (5) |
| Benefits paid                                                                                             | (23)            | (22) |
| Expenses paid                                                                                             | 0               | 0 |
| Currency translation adjustment                                                                           | 0               | 0 |
| Divestiture                                                                                               | 0               | 0 |
| Other                                                                                                     | 0               | 0 |
| Plan assets at end of fiscal year                                                                         | 265             | 242 |
| Funded status                                                                                             | $ 34            | $ 14 |

| X                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan, Plan Assets, Increase (Decrease) For Other Change
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of administration expense of defined benefit plan which decreases plan assets. Excludes plan administration expense paid by employer.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of increase in plan assets of defined benefit plan from business combination.
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| X                                                                                                                                                                                                                                                                                                                                                        |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
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No definition available.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of contribution received by defined benefit plan from employer which increases plan assets.
+ References
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of decrease in plan assets of defined benefit plan from disposal or classification as held-for-sale.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.
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