| **DISCONTINUED OPERATIONS - Additional Information (Details) - USD ($)**                                                          |               |               |               | 3 Months Ended | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|----------------|-----------------|
||
| **Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]** |          |          |          |           |            |   |
| Discontinued operations, per diluted share (in dollars per share)                                                                 |          |          |          |           | $ (0.02)        | $ (0.68) |
| Discontinued Operations, Disposed of by Sale | IT Services | Critical Networks                                                    |          |          |          |           |            |   |
| **Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]** |          |          |          |           |            |   |
| Proceeds from sale of discontinued operations, subject to post-closing adjustments, net                                           | $ 646,000,000 |          |          |           |            |   |
| Gain (loss) on sale of discontinued operations, before tax                                                                        | (28,000,000)  |          |          |           |            |   |
| Gain (loss) on disposal of discontinued operation, net of tax                                                                     | $ 55,000,000  |          |          |           |            |   |
| Discontinued operations, per diluted share (in dollars per share)                                                                 | $ 0.44        |          |          |           |            |   |
| Discontinued operation, period of continuing involvement after disposal                                                           | 18 months     |          |          |           |            |   |
| Goodwill assigned to disposal group                                                                                               |          |          |          | $ 487,000,000  |            |   |
| Non-cash impairment asset charge in discontinued operations                                                                       |          |          |          | 240,000,000    |            |   |
| Goodwill impairment loss                                                                                                          |          |          |          | $ 228,000,000  |            |   |
| Discontinued Operations, Disposed of by Sale | Caprock                                                                            |          |          |          |           |            |   |
| **Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]** |          |          |          |           |            |   |
| Proceeds from sale of discontinued operations, subject to post-closing adjustments, net                                           |          | $ 368,000,000 |          |           |            |   |
| Gain (loss) on sale of discontinued operations, before tax                                                                        |          | 14,000,000    |          |           |            |   |
| Gain (loss) on disposal of discontinued operation, net of tax                                                                     |          | $ 61,000,000  |          |           |            |   |
| Discontinued operations, per diluted share (in dollars per share)                                                                 |          | $ 0.49        |          |           |            |   |
| Discontinued Operations, Disposed of by Sale | Broadcast Communications                                                           |          |          |          |           |            |   |
| **Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]** |          |          |          |           |            |   |
| Asset sale agreement                                                                                                              |          |          | $ 225,000,000 |           |            |   |
| Cash consideration received on sale of disposal group                                                                             |          |          | 160,000,000   |           |            |   |
| Asset sale agreement promissory note                                                                                              |          |          | 15,000,000    |           |            |   |
| Asset sale agreement earnout                                                                                                      |          |          | $ 50,000,000  |           |            |   |

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.
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Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.
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Period of expected continuing involvement with a discontinued operation after the disposal date, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
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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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Per diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation.
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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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