Stock Options and Other Share-Based Compensation (Details) shares in Millions, $ in Millions	3 Months Ended
Apr. 02, 2021 USD ($) plan shares	Apr. 03, 2020 USD ($) shares
SIPs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shareholder approved employee stock incentive plans \| plan	2
L3Harris SIPs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation costs related to share-based awards \| $	$ 33	$ 17
Common stock issued, net of shares withheld for tax purposes (in shares)	0.1	0.5
Stock options granted (in shares)	0.5
L3Harris SIPs \| Restricted Sock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	0.1
L3Harris SIPs \| Performance Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted (in shares)	0.2
L3Harris SIPs \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	1.99%
Expected volatility	31.71%
Risk free interest rates	0.75%
Expected term	5 years 18 days

Number of shareholder approved employee stock incentive plans.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
-Topic 718
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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.

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Net number of share options (or share units) granted during the period.

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Number of shares issued under share-based payment arrangement.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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