Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Cash flows from operating activities
Net (loss) income	$ (16,782)	$ 18,463
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Realized loss on marketable debt securities	(22)	354
Depreciation and amortization	6,277	4,718
Amortization of debt discount	132	4
Amortization on right-of-use assets	421	343
Gain on sales of assets	(23)	(127)
Stock-based compensation expense	3,536	3,986
Change in fair value of investment securities	0	(174)
Accounts receivable allowances	718	(761)
Inventory valuation reserve	0	(78)
Credit loss expense, direct write-offs	91	6,163
Changes in operating assets and liabilities:
Accounts receivable	(68)	(4,498)
Inventory	135	702
Prepaid expenses and other current assets	(376)	(617)
Deferred tax asset	(7,313)	0
Other assets	0	(555)
Accounts payable and accrued expenses	3,478	(1,121)
Accrued diagnostic services	(695)	(881)
Accrued advertising and other allowances	(75)	(5)
Deferred revenue	(76)	619
Deferred tax liability	(224)	(138)
Lease liabilities	(181)	(301)
Income taxes payable	(912)	2,878
Other liabilities	611	(423)
Net cash (used in) provided by operating activities	(11,348)	28,551
Cash flows from investing activities
Business acquisitions, escrow received	478	0
Business acquisitions, net of cash acquired	(2,904)	0
Issuance of secured promissory note receivable	0	0
Purchase of marketable securities	(3,819)	(6,777)
Proceeds from sales of marketable securities	3,817	1,047
Proceeds from maturities of marketable securities	4,168	7,120
Proceeds from dispositions of property and other assets, net	46	452
Proceeds from promissory note	0	0
Capital expenditures	(3,155)	(3,919)
Net cash used in investing activities	(1,369)	(2,077)
Cash flows from financing activities
Proceeds from issuance of note payable	10,524	0
Proceeds from exercise of warrants	1,200	0
Repayment of common stock for payment of statutory taxes on cashless exercise of stock options	(5,379)	(7,474)
Repayment of note payable	0	(7,044)
Repurchases of common shares	(588)	(2,152)
Payment of dividends	0	(9,353)
Net cash provided by (used in) financing activities	5,757	(26,023)
(Decrease) increase in cash, cash equivalents and restricted cash	(6,960)	451
Cash, cash equivalents and restricted cash, at the beginning of the year	9,109	8,658
Cash, cash equivalents and restricted cash, at the end of the year	2,149	9,109
Supplemental disclosures:
Cash paid for income taxes	3,000	1,696
Interest payment on the promissory notes	932	763
Supplemental disclosure of non-cash investing and financing activities:
Stock-based compensation included in the prepaid expense	1,024	0
Issuance of common shares for debt conversion	2,400	600
Net unrealized loss, investments in marketable securities	1,520	1,294
Assets obtained in exchange for new finance lease obligations	5,809	0
Issuance of warrants with unsecured promissory note	398	0
Common stock issued in asset acquisition	$ 1,000	$ 0