LEGAL AND REGULATORY PROCEEDINGS (Details) - USD ($) $ in Thousands		6 Months Ended
	Jun. 24, 2024	Jun. 30, 2024	Jun. 30, 2023
Loss Contingencies [Line Items]
Cash funding received from Illumina		$ 1,244,300	$ 304,000
Illumina, Inc.
Loss Contingencies [Line Items]
Cash funding received from Illumina	$ 932,300
Clawback term on disposal funding	15 months
Grail, Inc. | Illumina, Inc.
Loss Contingencies [Line Items]
Percentage of shares retained after spin-off	14.50%