Note 9 - Revenue - Revenue by Major Source (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues	$ 5,175	$ 5,704	$ 15,260	$ 17,100
Testing [Member]
Revenues	4,421	4,864	12,900	14,416
Shipping/Collection (Hair) [Member]
Revenues	727	819	2,275	2,614
Other Revenue [Member]
Revenues	$ 27	$ 21	$ 85	$ 70

Amount, including 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