| **GOODWILL AND INTANGIBLE ASSETS - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Millions** | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Beginning Balance                                                                                             | $ 17,283        | $ 18,189 |
| Reallocation of goodwill in business realignment                                                              | 0               |   |
| Assets of business held for sale                                                                              | (9)             | (30) |
| Impairment of goodwill                                                                                        | 296             | 802 |
| Currency translation adjustments                                                                              | 27              | (74) |
| Ending Balance                                                                                                | 19,979          | 17,283 |
| Goodwill decrease from divestitures                                                                           | 9               | 30 |
| VIS Business                                                                                                  |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Assets of business held for sale                                                                              | (39)            |   |
| Goodwill decrease from divestitures                                                                           | 39              |   |
| Disposal Group, Held-for-sale, Not Discontinued Operations                                                    |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Disposal group, including discontinued operation, goodwill                                                    |            | 30 |
| Disposal Group, Held-for-sale, Not Discontinued Operations | VIS Business                                     |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Assets of business held for sale                                                                              | (9)             |   |
| Goodwill decrease from divestitures                                                                           | 9               |   |
| SAS                                                                                                           |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Beginning Balance                                                                                             | 5,778           | 5,849 |
| Reallocation of goodwill in business realignment                                                              | 327             |   |
| Assets of business held for sale                                                                              | (9)             | (30) |
| Impairment of goodwill                                                                                        | 0               | 0 |
| Currency translation adjustments                                                                              | 14              | (41) |
| Ending Balance                                                                                                | 6,110           | 5,778 |
| Goodwill decrease from divestitures                                                                           | 9               | 30 |
| Goodwill, impaired, accumulated impairment loss                                                               | 80              | 80 |
| IMS                                                                                                           |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Beginning Balance                                                                                             | 7,709           | 8,187 |
| Reallocation of goodwill in business realignment                                                              | (327)           |   |
| Assets of business held for sale                                                                              | (534)           | 0 |
| Impairment of goodwill                                                                                        | 296             | 447 |
| Currency translation adjustments                                                                              | 12              | (31) |
| Ending Balance                                                                                                | 6,564           | 7,709 |
| Goodwill decrease from divestitures                                                                           | 534             | 0 |
| Goodwill, impaired, accumulated impairment loss                                                               | 1,126           | 830 |
| CS                                                                                                            |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Beginning Balance                                                                                             | 3,796           | 4,153 |
| Reallocation of goodwill in business realignment                                                              | 0               |   |
| Goodwill from acquisition                                                                                     | 1,143           |   |
| Assets of business held for sale                                                                              |            | 0 |
| Impairment of goodwill                                                                                        | 0               | 355 |
| Currency translation adjustments                                                                              | 1               | (2) |
| Ending Balance                                                                                                | 4,940           | 3,796 |
| Goodwill decrease from divestitures                                                                           |            | 0 |
| Goodwill, impaired, accumulated impairment loss                                                               | 355             | $ 355 |
| AR                                                                                                            |            |   |
| **Goodwill [Roll Forward]**                                                                                   |            |   |
| Reallocation of goodwill in business realignment                                                              | 0               |   |
| Goodwill from acquisition                                                                                     | 2,365           |   |
| Impairment of goodwill                                                                                        | 0               |   |
| Currency translation adjustments                                                                              | 0               |   |
| Ending Balance                                                                                                | $ 2,365         |   |

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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount classified as goodwill attributable to disposal group held for sale or disposed of.
+ References
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| - Definition
Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - Definition
Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.
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| - Definition
Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - Definition
Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - Definition
Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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| - Definition
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| - Definition
Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.
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