Fair value measurements - Summary of Activity Related to Equity Investments (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 28, 2026	Dec. 28, 2025
Equity Investment [Roll Forward]
Non Current Other Assets	$ 14,269	$ 14,368
Equity Securities \| Equity Investments with readily determinable value
Equity Investment [Roll Forward]
Carrying value, beginning of period	665
Equity, Fair Value Adjustment	190
Sales/ Purchases/Other	(52)
Carrying value, end of period	803
Non Current Other Assets	803
Equity Securities \| Equity Investments without readily determinable value
Equity Investment [Roll Forward]
Carrying value, beginning of period	910
Equity, Fair Value Adjustment	40
Sales/ Purchases/Other	(118)
Carrying value, end of period	832
Non Current Other Assets	$ 832

Equity Investment [Roll Forward]

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- Definition

Amount of addition (reduction) to the amount at which an instrument classified in shareholders' equity could be incurred (settled) in a current transaction between willing parties.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
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- Definition

Amount of investment in equity security without readily determinable fair value.

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- Definition

Amount of investment in marketable security, classified as noncurrent.

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Amount of noncurrent assets classified as other.

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