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Investments (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
Investments (Details) - USD ($) $ in Millions	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020	Dec. 31, 2020
Investments
Total trading short-term investments	$ 1,483		$ 1,483		$ 1,465
Change in unrealized gains (losses) on trading securities	9	$ 113	17	$ (97)
Denominated in foreign currencies
Investments
Total trading short-term investments	45		45		29
Domestic debt securities
Investments
Fair Value	685		685		496
Domestic equity securities
Investments
Fair Value	456		456		702
Foreign equity securities
Investments
Fair Value	193		193		133
Foreign debt securities
Investments
Fair Value	117		117		68
Money market funds held in trading accounts
Investments
Fair Value	15		15		47
Other trading securities
Investments
Fair Value	$ 17		$ 17		$ 19