Income taxes - Temporary Differences and Carryforwards (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Jan. 01, 2023
Asset
Employee related obligations	$ 586	$ 685
Stock based compensation	686	632
R&D capitalized for tax	3,595	2,611
Reserves & liabilities	3,816	2,733
Income reported for tax purposes	359	2,026
Net realizable operating loss carryforwards	996	1,319
Undistributed foreign earnings	1,801	1,517
Miscellaneous international	831	861
Miscellaneous U.S.		452
Total deferred income taxes	12,670	12,836
Liability
Depreciation of property, plant and equipment	(902)	(845)
Goodwill and intangibles	(1,252)	(1,737)
Undistributed foreign earnings	(1,695)	(1,604)
Global intangible low-taxed income	(2,731)	(3,628)
Miscellaneous international		(66)
Miscellaneous U.S.	(4)
Total deferred income taxes	(6,584)	(7,880)
Operating loss carryforwards, valuation allowance	1,100	$ 800
Increase in valuation allowance	$ 100

Deferred tax assets international research and development capitalized.

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Deferred tax assets other domestic.

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Deferred Tax Assets, Undistributed Foreign Earnings

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Deferred Tax Liabilities, Other Domestic

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Deferred Tax Liability, Global Intangible Low-Taxed Income

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-6

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-Topic 740
-SubTopic 10
-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-8

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible foreign operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences from employee benefits, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences classified as other.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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Amount of deferred tax liability attributable to taxable temporary differences from undistributed earnings of subsidiary and other recognized entity not within country of domicile. Includes, but is not limited to, other basis differences.

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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 740
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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
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