| **ACCUMULATED OTHER COMPRENSIVE LOSS - Additional Information (Details) - USD ($) $ in Millions**                                   |        | 3 Months Ended | 12 Months Ended |
|-------------------------------------------------------------------------------------------------------------------------------------|--------|----------------|-----------------|
||
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]**                                          |   |           |            |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings | $ 35   | $ 35           | $ 0             |
| Accumulated Defined Benefit Plans Adjustment Attributable to Parent                                                                 |   |           |            |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]**                                          |   |           |            |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings | 30     |           |            |
| Accumulated Net Investment Gain (Loss) Attributable to Parent                                                                       |   |           |            |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]**                                          |   |           |            |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings | 4      |           |            |
| Accumulated Foreign Currency Adjustment Attributable to Parent                                                                      |   |           |            |
| **Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]**                                          |   |           |            |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings | $ 1    |           |            |

| X                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings
+ References
No definition available.
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                      |
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| X                                                                                                                                                                            |
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