| **PENSION AND OTHER POSTRETIREMENT BENEFITS - Reconciliation of Defined Benefit Plan Asset Balances (Details) - USD ($) $ in Millions** | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | $ 5,133         | $ 4,489 |
| Plan assets at end of fiscal year                                                                                                       | 5,305           | 5,133 |
| Level 3                                                                                                                                 |            |   |
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | 766             | 984 |
| Realized gains (losses), net                                                                                                            | 55              | 55 |
| Unrealized gains (losses), net                                                                                                          | (29)            | (22) |
| Sales, net                                                                                                                              | (192)           | (251) |
| Plan assets at end of fiscal year                                                                                                       | 600             | 766 |
| Level 3 | Private equity funds                                                                                                          |            |   |
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | 522             | 700 |
| Realized gains (losses), net                                                                                                            | 47              | 78 |
| Unrealized gains (losses), net                                                                                                          | (25)            | (71) |
| Sales, net                                                                                                                              | (144)           | (185) |
| Plan assets at end of fiscal year                                                                                                       | 400             | 522 |
| Level 3 | Hedge funds                                                                                                                   |            |   |
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | 242             | 282 |
| Realized gains (losses), net                                                                                                            | 8               | (23) |
| Unrealized gains (losses), net                                                                                                          | (4)             | 49 |
| Sales, net                                                                                                                              | (59)            | (66) |
| Plan assets at end of fiscal year                                                                                                       | 187             | 242 |
| Level 3 | Fixed Income funds                                                                                                            |            |   |
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | 0               | 0 |
| Realized gains (losses), net                                                                                                            | 0               | 0 |
| Unrealized gains (losses), net                                                                                                          | 0               | 0 |
| Sales, net                                                                                                                              | 11              | 0 |
| Plan assets at end of fiscal year                                                                                                       | 11              | 0 |
| Level 3 | Other                                                                                                                         |            |   |
| **Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward]**                                    |            |   |
| Plan assets at beginning of fiscal year                                                                                                 | 2               | 2 |
| Realized gains (losses), net                                                                                                            | 0               | 0 |
| Unrealized gains (losses), net                                                                                                          | 0               | 0 |
| Sales, net                                                                                                                              | 0               | 0 |
| Plan assets at end of fiscal year                                                                                                       | $ 2             | $ 2 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets sold.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.
+ References
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| - Definition
A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.
+ References
No definition available.
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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.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.
+ References
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