Significant Accounting Policies and Recent Accounting Standards - L3Harris Merger-related Expenses (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 02, 2021	Jul. 03, 2020	Jul. 02, 2021	Jul. 03, 2020
Business Acquisition [Line Items]
Integration costs, recognized as incurred	$ 20	$ 37	$ 41	$ 68
L3Harris
Business Acquisition [Line Items]
Additional cost of sales related to fair value step-up in inventory sold	0	16	0	31
Restructuring charges	0	7	0	7
Integration costs, recognized as incurred	20	37	41	68
Total L3Harris Merger-related expenses	$ 20	$ 60	$ 41	$ 106

Business Combination, Amortization Of Inventory Step-up

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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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Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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