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RELATED PARTY TRANSACTIONS - Narrative (Details) - Grail, Inc. - Illumina, Inc. - shares	Sep. 30, 2025	Jun. 24, 2024
Related Party Transaction [Line Items]
Percentage of shares retained after spin-off (as a percent)	12.50%	14.50%
Spinoff transaction number of shares distributed (in shares)	4,502,126

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