| **Business Combinations - Consideration Paid for Exelis (Details) - USD ($) $ in Millions** |         | 12 Months Ended |
|---------------------------------------------------------------------------------------------|---------|-----------------|
||
| **Business Acquisition [Line Items]**                                                       |    |            |   |   |
| Net cash consideration paid                                                                 |    | $ 0             | $ 3,186 | $ 0 |
| Exelis                                                                                      |    |            |   |   |
| **Business Acquisition [Line Items]**                                                       |    |            |   |   |
| Cash consideration paid for Exelis outstanding common stock                                 | $ 3,128 |            |   |   |
| Cash consideration paid for Exelis outstanding stock options                                | 125     |            |   |   |
| Cash consideration paid for Exelis outstanding restricted stock units                       | 38      |            |   |   |
| Cash consideration paid for dividends to Exelis shareholders                                | 21      |            |   |   |
| Total cash consideration paid                                                               | 3,312   |            |   |   |
| Less cash acquired                                                                          | (130)   |            |   |   |
| Net cash consideration paid                                                                 | 3,182   |            |   |   |
| Fair value of Harris common stock issued for Exelis common stock                            | 1,527   |            |   |   |
| Total net purchase price paid                                                               | $ 4,709 |            |   |   |

| X                                                                                                                                                                                                                                                                  |
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Payments To Acquire Businesses Dividends
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Payments To Acquire Businesses Outstanding Common Stock
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Payments To Acquire Businesses Outstanding Restricted Stock Units
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| - Definition
Payments To Acquire Businesses Outstanding Stock Options
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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.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.
+ References
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| - Definition
The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).
+ References
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| - Definition
The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.
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| - Definition
The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.
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