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ORGANIZATION AND DESCRIPTION OF BUSINESS (Details) - USD ($) $ in Thousands	34 Months Ended
	Jun. 23, 2024	Mar. 31, 2026	Dec. 31, 2025	Mar. 31, 2025
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash equivalents in money market accounts		$ 69,344	$ 249,727	$ 133,895
Short-term marketable securities		$ 753,761	$ 654,703
SDG Ops, LLC \| Illumina, Inc.
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percentage ownership prior to spin-off (as a percent)	100.00%