| **ACCOUNTING CHANGES OR RECENT ACCOUNTING PRONOUNCEMENTS - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions** |        | 3 Months Ended | 12 Months Ended |          |        |
|--------------------------------------------------------------------------------------------------------------------------------------------|--------|----------------|-----------------|----------|--------|
||
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Reduction in prepaid income taxes                                                                                                          |   | $ (483)        | $ (483)         | $ (952)  |   |   |
| Non-current deferred income taxes                                                                                                          |   | 119            | 119             | 424      |   |   |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings        | $ 35   | $ 35           | 0               |     |   |   |
| Increase in cost of sales and services                                                                                                     |   |           | 4,066           | 3,854    |   |   |
| Increase in engineering, selling and administrative expenses                                                                               |   |           | 1,182           | 1,150    |   |   |
| Increase in non-operating income                                                                                                           |   |           | 156             | 166      |   |   |
| Retained Earnings                                                                                                                          |   |           |            |     |   |   |
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Reclassification of stranded tax effects of Tax and Jobs Act of 2017 from accumulated other comprehensive loss to retained earnings        |   |           | 35              |     |   |   |
| Intra-entity Transfers of Assets Other Than Inventory                                                                                      |   |           |            |     |   |   |
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Reduction in prepaid income taxes                                                                                                          |   |           |            |     | $ 27   |   |
| Non-current deferred income taxes                                                                                                          |   |           |            |     | $ 27   |   |
| ASC 606                                                                                                                                    |   |           |            |     |   |   |
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Decrease in revenue from product sales and services                                                                                        |   |           | 14              | 3        |   |   |
| Operating income (loss)                                                                                                                    |   |           | $ (19)          | $ (10)   |   |   |
| Operating income (loss), per diluted share (in dollars per share)                                                                          |   |           | $ (0.15)        | $ (0.08) |   |   |
| ASC 606 | Retained Earnings                                                                                                                |   |           |            |     |   |   |
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Cumulative effect adjustment as reduction of opening balance of retained earnings                                                          |   |           |            |     |   | $ 15 |
| ASU 2017-07                                                                                                                                |   |           |            |     |   |   |
| **Business Combination, Separately Recognized Transactions [Line Items]**                                                                  |   |           |            |     |   |   |
| Increase in cost of sales and services                                                                                                     |   |           | $ 147           | $ 132    |   |   |
| Increase in engineering, selling and administrative expenses                                                                               |   |           | 37              | 32       |   |   |
| Increase in non-operating income                                                                                                           |   |           | $ 184           | $ 164    |   |   |

| X                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Operating Income (Loss), Per Diluted Share
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Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings
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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.
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| - Definition
The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.
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| - Definition
Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.
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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.
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| - Definition
Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.
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| - Definition
The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).
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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.
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The net result for the period of deducting operating expenses from operating revenues.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).
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