| **Business Combinations - Pro Forma Results (Unaudited) (Details) - USD ($) $ in Millions** | 12 Months Ended |
|---------------------------------------------------------------------------------------------|-----------------|
||
| **Business Acquisition [Line Items]**                                                       |            |   |   |
| Revenue from product sales and services - as reported                                       | $ 7,467         | $ 5,083 | $ 5,012 |
| Income from continuing operations - as reported                                             | $ 345           | 334 | 540 |
| Exelis | As Reported                                                                        |            |   |   |
| **Business Acquisition [Line Items]**                                                       |            |   |   |
| Revenue from product sales and services - as reported                                       |            | 5,083 | 5,012 |
| Income from continuing operations - as reported                                             |            | 334 | 540 |
| Exelis | Pro Forma                                                                          |            |   |   |
| **Business Acquisition [Line Items]**                                                       |            |   |   |
| Revenue from product sale and services - pro forma                                          |            | 8,085 | 8,287 |
| Income from continuing operations - pro forma                                               |            | $ 455 | $ 707 |

| X                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - 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
Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount after tax of income (loss) from continuing operations attributable to the parent.
+ References
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.
+ References
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