| **ACQUISITIONS AND DIVESTITURES - Acquisition of AJRD - Narrative (Details) - USD ($) $ in Millions** |         | 3 Months Ended | 6 Months Ended |          |
|-------------------------------------------------------------------------------------------------------|---------|----------------|----------------|----------|
||
| **Business Acquisition [Line Items]**                                                                 |    |           |           |     |   |   |
| Goodwill                                                                                              |    | $ 20,367       |           | $ 20,367 |   | $ 19,979 |
| 5.4% Notes Due 2027 and 2033 and 5.6% Notes Due 2053 | Fixed-rate debt                                |    |           |           |     |   |   |
| **Business Acquisition [Line Items]**                                                                 |    |           |           |     |   |   |
| Proceeds from issuance of long-term debt                                                              | $ 3,250 |           |           |     |   |   |
| Aerojet Rocketdyne Holdings, Inc.                                                                     |    |           |           |     |   |   |
| **Business Acquisition [Line Items]**                                                                 |    |           |           |     |   |   |
| Business acquisition, percentage of ownership                                                         | 100.00% |           |           |     |   |   |
| Business combination, consideration transferred                                                       | $ 4,715 |           |           |     |   |   |
| Provision for loss on customer contracts                                                              |    | 357            |           | 357      |   |   |
| Loss provision amortization expense                                                                   |    | 47             |           | 61       |   |   |
| Liabilities assumed                                                                                   |    | 194            |           | 194      |   |   |
| Revenue from amortization of off-market contract liability                                            |    | 22             |           | 30       |   |   |
| Goodwill                                                                                              | $ 2,348 | 2,861          |           | 2,861    |   |   |
| Acquisition related costs                                                                             |    | 16             | $ 13           | 44       | $ 22 |   |
| Aerojet Rocketdyne Holdings, Inc. | Other Accrued Liabilities                                         |    |           |           |     |   |   |
| **Business Acquisition [Line Items]**                                                                 |    |           |           |     |   |   |
| Liabilities assumed                                                                                   |    | 49             |           | 49       |   |   |
| Aerojet Rocketdyne Holdings, Inc. | Other Noncurrent Liabilities                                      |    |           |           |     |   |   |
| **Business Acquisition [Line Items]**                                                                 |    |           |           |     |   |   |
| Liabilities assumed                                                                                   |    | $ 145          |           | $ 145    |   |   |

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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Off-Market Customer Contracts, Net Liability
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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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Percentage of voting equity interests acquired at the acquisition date in the business combination.
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This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.
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Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.
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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.
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