STOCK-BASED COMPENSATION - Stock-based compensation expense (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	$ 58,283	$ 86,084	$ 97,235
Related income tax benefits	(13,708)	(20,890)	(23,455)
Stock-based compensation expense, net of taxes	44,575	65,194	73,780
RSUs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	54,564	29,774	1,127
Shares issuable under ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	3,059	0	0
PSOs
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	660	1,514	577
Cash-based equity awards
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	0	54,796	95,531
Cost of screening revenue (exclusive of amortization of intangible assets)
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	2,226	1,724	1,932
Cost of development services revenue
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	36	230	38
Research and development
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	15,986	30,701	39,792
Sales and marketing
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	10,871	15,310	17,506
General and administrative
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Stock-based compensation expense, before taxes	$ 29,164	$ 38,119	$ 37,967

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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