| **DEBT - Debt Issued Prior to 2020 Still Outstanding (Details) - USD ($) $ in Millions** | Apr. 27, 2015 | Dec. 03, 2010 | Jan. 03, 2020 | Feb. 01, 2008 | Dec. 05, 2007 | Feb. 28, 1998 | Jan. 31, 1996 |
|------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|---------------|---------------|---------------|
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            | $ 2,400       |          |          |          |          |          |          |
| Exelis Notes                                                                             |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Debt instrument redemption price percentage                                              | 100.00%       |          |          |          |          |          |          |
| 3.832% notes, due April 27, 2025                                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          |          | $ 600         |          |          |          |          |
| Debt interest rate                                                                       |          |          | 3.832%        |          |          |          |          |
| 4.854% notes, due April 27, 2035                                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          |          | $ 400         |          |          |          |          |
| Debt interest rate                                                                       |          |          | 4.854%        |          |          |          |          |
| 5.054% notes, due April 27, 2045                                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          |          | $ 500         |          |          |          |          |
| Debt interest rate                                                                       |          |          | 5.054%        |          |          |          |          |
| 6.15% notes, due December 15, 2040                                                       |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          | $ 300         |          |          |          |          |          |
| Debt interest rate                                                                       |          | 6.15%         |          |          |          |          |          |
| Debt instrument redemption price percentage                                              |          | 100.00%       |          |          |          |          |          |
| Debt instrument redemption price percentage of principal amount                          |          | 101.00%       |          |          |          |          |          |
| Interest rate margin                                                                     |          | 0.35%         |          |          |          |          |          |
| 7.0% debentures, due January 15, 2026                                                    |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          |          |          |          |          |          | $ 100         |
| Debt interest rate                                                                       |          |          |          |          |          |          | 7.00%         |
| 6.35% debentures, due February 1, 2028                                                   |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Notes payable                                                                            |          |          |          |          |          | $ 150         |          |
| Debt interest rate                                                                       |          |          |          |          |          | 6.35%         |          |
| Repurchased and retire principal amount of debentures                                    |          |          |          |          | $ 25          |          |          |
| Redemption of debentures                                                                 |          |          | $ 26          | $ 99          |          |          |          |
| External Credit Rating, Investment Grade | Exelis Notes                                  |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Debt instrument redemption price percentage of principal amount                          | 101.00%       |          |          |          |          |          |          |
| Treasury Rate | 3.832% notes, due April 27, 2025                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Interest rate margin                                                                     | 0.30%         |          |          |          |          |          |          |
| Treasury Rate | 4.854% notes, due April 27, 2035                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Interest rate margin                                                                     | 0.35%         |          |          |          |          |          |          |
| Treasury Rate | 5.054% notes, due April 27, 2045                                         |          |          |          |          |          |          |          |
| **Debt Instrument [Line Items]**                                                         |          |          |          |          |          |          |          |
| Interest rate margin                                                                     | 0.40%         |          |          |          |          |          |          |

| X                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Redemption of debentures.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                           |
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Repurchased and retired principal amount of debentures.
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| X                                                                                                                                                                                                                                                                                                                                 |
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| - Definition
Percentage points added to the reference rate to compute the variable rate on the debt instrument.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
+ References
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| - Definition
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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.
+ References
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| X                                                                                                                                                                                                                                                                                                       |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Percentage of principal amount of debt redeemed.
+ References
No definition available.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.
+ References
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