Fair Value Measurements - Summary of Derivative Activity (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 03, 2021	Dec. 29, 2019
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	12	(54)
Amount of gain or (loss) recognized in AOCI	44	(20)
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	(329)	(321)
Amount of gain or (loss) recognized in AOCI	298	(606)
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	(137)	(105)
Amount of gain or (loss) recognized in AOCI	(191)	(94)
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	153	159
Amount of gain or (loss) recognized in AOCI	153	159
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	370	292
Amount of gain or (loss) recognized in AOCI	748	417
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 \| 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	(16)	22
Amount of gain or (loss) recognized in AOCI	$ (52)	$ 39

Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

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