v3.25.4

INVESTMENTS AND FAIR VALUE MEASUREMENTS - Schedule of Marketable Equity Securities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2025	Dec. 29, 2024	Dec. 31, 2023
Marketable Securities [Line Items]
Net gains (losses) recognized during the period	$ 315	$ (310)	$ (2)
Less: Net gains (losses) recognized during the period on securities disposed of during the period	150	0	(2)
Net unrealized gains (losses) recognized during the period on securities still held at the reporting date	$ 165	(310)	$ 0
Spinoff \| GRAIL
Marketable Securities [Line Items]
Discontinued operation, gain (loss) on disposal of discontinued operation, net of tax		$ (309)
Discontinued Operation, Gain (Loss) on Disposal, Statement of Income or Comprehensive Income Flag		Other Nonoperating Income (Expense)

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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+ References

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Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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No definition available.

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ILLUMINA, INC. 10-K