Special Charges - Restructuring reserve activity and total expected cash outlay (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Jan. 01, 2022
Restructuring reserve activity
Balance at beginning of period	$ 28	$ 52
Cash paid	(15)	(36)
Reversals		(6)
Foreign currency translation	(1)	(1)
Balance at end of period	12	28
COVID-19 Restructuring Plan
Restructuring reserve activity
Provision for plan		19
Severance Costs
Restructuring reserve activity
Balance at beginning of period	19	43
Cash paid	(13)	(27)
Reversals		(5)
Foreign currency translation	(1)	(1)
Balance at end of period	5	19
Severance Costs | COVID-19 Restructuring Plan
Restructuring reserve activity
Provision for plan		9
Contract Terminations and Other
Restructuring reserve activity
Balance at beginning of period	9	9
Cash paid	(2)	(9)
Reversals		(1)
Foreign currency translation	0	0
Balance at end of period	$ 7	9
Contract Terminations and Other | COVID-19 Restructuring Plan
Restructuring reserve activity
Provision for plan		$ 10