Fair value measurements - Schedule of Effect of Derivatives not Designated as Hedging Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Jan. 01, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Other Nonoperating Income (Expense)	Other Nonoperating Income (Expense)
Forward foreign exchange contracts: | Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Gain/(Loss) Recognized In Income on Derivative	$ (60)	$ 94