Fair value measurements - Summary of Derivative Activity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2024	Dec. 31, 2023	Jan. 01, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	$ 862	$ 569	$ 348
Amount of gain or (loss) recognized in AOCI	(511)	422	$ 454
Sales | Interest Rate Swap | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Sales | Cross currency interest rate swaps contracts: | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Sales | Cross currency interest rate swaps contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Sales | Forward foreign exchange contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	2	7
Amount of gain or (loss) recognized in AOCI	(7)	10
Cost of Products Sold | Interest Rate Swap | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Cost of Products Sold | Cross currency interest rate swaps contracts: | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Cost of Products Sold | Cross currency interest rate swaps contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Cost of Products Sold | Forward foreign exchange contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	426	186
Amount of gain or (loss) recognized in AOCI	(156)	447
R&D Expense | Interest Rate Swap | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
R&D Expense | Cross currency interest rate swaps contracts: | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
R&D Expense | Cross currency interest rate swaps contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	0	0
Amount of gain or (loss) recognized in AOCI	0	0
R&D Expense | Forward foreign exchange contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	33	(37)
Amount of gain or (loss) recognized in AOCI	80	(18)
Interest (Income) Expense | Interest Rate Swap | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	64	168
Amount of gain or (loss) recognized in AOCI	(64)	(168)
Interest (Income) Expense | Cross currency interest rate swaps contracts: | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	148	130
Amount of gain or (loss) recognized in AOCI	148	130
Interest (Income) Expense | Cross currency interest rate swaps contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	247	275
Amount of gain or (loss) recognized in AOCI	(597)	(156)
Interest (Income) Expense | Forward foreign exchange contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Other (Income) Expense | Interest Rate Swap | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Other (Income) Expense | Cross currency interest rate swaps contracts: | Fair Value Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in income on derivative amount excluded from effectiveness testing	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Other (Income) Expense | Cross currency interest rate swaps contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	0	0
Amount of gain or (loss) recognized in AOCI	0	0
Other (Income) Expense | Forward foreign exchange contracts: | Cash Flow Hedging
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) reclassified from AOCI into income	6	8
Amount of gain or (loss) recognized in AOCI	$ 21	$ 9