Supplemental Financial Statement Data Allowance for doubtful accounts (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Disclosure Text Block Supplement [Abstract]
Balance at beginning of year	$ 10	$ 10	$ 10
Additions charged to expense	13	9	4
Doubtful accounts charged to reserve	(4)	(9)	(4)
Balance at end of year	$ 19	$ 10	$ 10