Stockholders' Equity - Summary of Share-based Compensation Expense for all Stock Awards (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 03, 2021	Dec. 29, 2019	Dec. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, before taxes	$ 194	$ 194	$ 193
Related income tax benefits	(43)	(41)	(39)
Share-based compensation expense, net of taxes	151	153	154
Cost of product revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, before taxes	21	19	16
Cost of service and other revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, before taxes	4	4	3
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, before taxes	74	66	60
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense, before taxes	$ 95	$ 105	$ 114

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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