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Stockholders' Equity Note, Spinoff Transaction, Percent Of Shares Outstanding Distributed

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- Definition

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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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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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.

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Number of shares of investment owned.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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ORGANIZATION AND DESCRIPTION OF BUSINESS (Details) - USD ($) $ in Thousands		12 Months Ended			34 Months Ended
	Jun. 24, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jun. 23, 2024
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash funding received from Illumina		$ 0	$ 1,244,300	$ 464,000
Cash deposits and cash equivalents		249,727	214,234	$ 97,287
Short-term marketable securities		$ 654,703	$ 549,236
Illumina, Inc.
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percent of shares distributed in spin-off (as a percent)	85.50%
Stockholders' equity note, spinoff transaction, number of shares distributed (in shares)	31,000,000.0
Illumina, Inc.
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Cash funding received from Illumina	$ 932,300
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%
Grail, Inc. \| Illumina, Inc.
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Shares owned (in shares)	4,502,126
Percentage of shares retained after spin-off (as a percent)	14.50%	6.00%