| **Debt - Debt Exchange (Details) - Senior unsecured debt $ in Millions**      | Jul. 02, 2019 USD ($) | Jul. 01, 2019 USD ($) |
|-------------------------------------------------------------------------------|-----------------------|-----------------------|
| L3Harris                                                                      |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                | $ 3,350               |                  |
| Debt conversion ratio, debt to be exchanged for cash                          | 0.001                 |                  |
| Aggregate principal amount of new l3harris notes issued                       | $ 3,021               |                  |
| 4.95% notes due February 15, 2021 (“4.95% 2021 Notes”) | L3Harris |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Debt conversion rate                                                          | 4.95%                 | 4.95%                 |
| Aggregate principal amount of new l3harris notes issued                       | $ 501                 |                  |
| 3.85% notes due June 15, 2023 (“3.85% 2023 Notes”) | L3Harris     |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Debt conversion rate                                                          | 3.85%                 | 3.85%                 |
| Aggregate principal amount of new l3harris notes issued                       | $ 741                 |                  |
| 3.95% notes due May 28, 2024 (“3.95% 2024 Notes”) | L3Harris      |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Debt conversion rate                                                          | 3.95%                 | 3.95%                 |
| Aggregate principal amount of new l3harris notes issued                       | $ 326                 |                  |
| 3.85% notes due December 15, 2026 (“3.85% 2026 Notes”) | L3Harris |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Debt conversion rate                                                          | 3.85%                 | 3.85%                 |
| Aggregate principal amount of new l3harris notes issued                       | $ 535                 |                  |
| 4.40% notes due June 15, 2028 (“4.40% 2028 Notes”) | L3Harris     |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Debt conversion rate                                                          | 4.40%                 | 4.40%                 |
| Aggregate principal amount of new l3harris notes issued                       | $ 918                 |                  |
| L3                                                                            |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | $ 3,350               |
| Long-term Debt                                                                | 329                   |                  |
| L3 | 4.95% notes due February 15, 2021 (“4.95% 2021 Notes”)       |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | 650                   |
| Long-term Debt                                                                | 149                   |                  |
| L3 | 3.85% notes due June 15, 2023 (“3.85% 2023 Notes”)           |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | 800                   |
| Long-term Debt                                                                | 59                    |                  |
| L3 | 3.95% notes due May 28, 2024 (“3.95% 2024 Notes”)            |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | 350                   |
| Long-term Debt                                                                | 24                    |                  |
| L3 | 3.85% notes due December 15, 2026 (“3.85% 2026 Notes”)       |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | 550                   |
| Long-term Debt                                                                | 15                    |                  |
| L3 | 4.40% notes due June 15, 2028 (“4.40% 2028 Notes”)           |                  |                  |
| **Debt Instrument, Redemption [Line Items]**                                  |                  |                  |
| Original debt amount converted                                                |                  | $ 1,000               |
| Long-term Debt                                                                | $ 82                  |                  |

| X                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Debt Exchange Offer, Conversion Ratio, Debt To Be Exchanged For Cash
+ References
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| - Definition
The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.
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| - Definition
Dividend or interest rate associated with the financial instrument issued in exchange for the original debt being converted in a noncash or part noncash transaction. Noncash are transactions that affect recognized assets or liabilities but that do not result in cash receipts or cash payments. Part noncash refers to that portion of the transaction not resulting in cash receipts or cash payments.
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| - Definition
The amount of the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.
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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, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
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