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

Debt Exchange Offer, Conversion Ratio, Debt To Be Exchanged For Cash

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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
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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.

+ References

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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.

+ References

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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.

+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
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-Publisher FASB
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