Fair value measurements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 29, 2026	Dec. 28, 2025
Derivative [Line Items]
Accumulated other comprehensive loss on derivatives, after tax	$ (600)
Hedging exposure	18 months
Weighted average interest rate on non-current debt	3.56%
Excess of carrying value over fair value of debt		$ 1,700
Current Debt	$ 17,460	8,495
Cash and Cash Equivalents	21,688	19,709
Money market funds \| Fair Value, Inputs, Level 1 [Member]
Derivative [Line Items]
Cash and Cash Equivalents	5,089	5,993
Commercial Paper
Derivative [Line Items]
Current Debt	$ 15,700	$ 6,500
Weighted average interest rate	3.67%	3.81%
Term	2 months	2 months
Forward foreign exchange contracts
Derivative [Line Items]
Collateral already posted, aggregate fair value	$ 4,700
Derivative, notional amount	43,900	$ 40,600
Cross currency interest rate swaps
Derivative [Line Items]
Derivative, notional amount	37,900	38,900
Interest Rate Swap
Derivative [Line Items]
Derivative, notional amount	$ 8,000	$ 8,000

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Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal or face amount used to calculate payment on derivative.

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Weighted average interest rate of long-term debt outstanding calculated at point in time.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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