Reportable Segment and Geographic Information - Summary of Revenue by Geographic Region (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Segment Reporting Information [Line Items]
Revenue	$ 84,069	$ 71,743	$ 239,335	$ 207,256
Operating Segments
Segment Reporting Information [Line Items]
Revenue	84,069	71,743	239,335	207,256
United States \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	77,608	65,703	221,641	189,052
China \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	3,128	2,785	8,146	9,366
Other countries \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	3,333	3,255	9,548	8,838
Foreign \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	$ 6,461	$ 6,040	$ 17,694	$ 18,204

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

Fulgent Genetics, Inc. 10-Q