STOCK OPTIONS AND OTHER SHARE-BASED COMPENSATION - Narrative (Details) shares in Millions, $ in Millions	3 Months Ended
Apr. 01, 2022 USD ($) plan shares	Apr. 02, 2021 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shareholder approved employee stock incentive plans \| plan	2
L3Harris Shareholder-approved Employee Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based payment arrangement, expense \| $	$ 28	$ 33
Common stock issued, net of shares withheld for tax purposes (in shares)	0.4	0.1
Options granted (in shares)	0.4
Performance Share Units \| L3Harris Shareholder-approved Employee Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options granted (in shares)	0.2
Restricted Stock Units \| L3Harris Shareholder-approved Employee Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity instruments other than options granted (in shares)	0.2
Stock Options \| L3Harris Shareholder-approved Employee Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend rate	1.92%
Expected volatility rate	29.11%
Risk free interest rate	1.86%
Expected term	5 years 7 days

Number of shareholder-approved employee stock incentive plans.

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

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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).

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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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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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