CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Cash flows from operating activities
Net income	$ 6,815	$ 6,476
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization (including $304 and $303 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	2,688	2,629
Adjustments to allowance for bad debt	222	(12)
Adjustments to inventory reserve	90	40
(Recovery) write-off of inventory	(83)	293
Impairment of operating right-of-use asset	0	1,993
(Gain) loss, net, on disposal of property and equipment	(17)	1
Amortization of loan fees (including $15 associated with variable interest entity for both the three months ended March 31, 2025 and 2024)	23	23
Accrued interest on certificates of deposit (including $0 and $38 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(48)	(126)
Unrealized loss from investment in publicly-traded equity securities	46	0
Stock-based compensation	346	375
Amortization of operating right-of-use assets	2,253	1,466
Government grant income (including $8 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(18)	0
(Increase) decrease in operating assets
Accounts receivable	(5,887)	(2,336)
Inventories	(9,191)	(8,077)
Prepaid expenses and other current assets (including $112 and $4 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	257	1,727
Other non-current assets (including $25 and $14 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(24)	(190)
Increase (decrease) in operating liabilities
Accounts payable (including $3 and $5 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	6,734	3,367
Accrued expenses (including $303 and $420 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	1,313	742
Related party payable	1,927	(6)
Income taxes payable (including $3 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	2,124	0
Deferred revenue	395	(507)
Operating lease liabilities	(2,337)	(1,474)
Other liabilities (including $59 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	98	155
Net cash provided by operating activities	7,726	6,559
Cash flows from investing activities
Purchases of property and equipment	(107)	(163)
Proceeds from disposal of property and equipment	59	23
Deposits paid for property and equipment	(989)	(761)
Purchases of publicly-traded equity securities	(212)	0
Proceeds from disposal of publicly-traded equity securities	191	0
Purchases of short-term investments (including $87 and $7,000 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(8,148)	(12,190)
Redemption of short-term investments (including $7,678 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	12,739	5,144
Net cash provided by (used in) investing activities	3,533	(7,947)
Cash flows from financing activities
Payment of long-term debt (including $295 and $278 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(295)	(278)
Payments for lender fees	(47)	0
Proceeds from exercise of common stock options	0	52
Dividends paid to shareholders	(9,017)	(5,992)
Payment of Global Wells noncontrolling-interest tax withholding (including $132 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(132)	0
Payment of Global Wells noncontrolling membership interest redemption (including $0 and $2,010 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	0	(2,326)
Payment of Global Wells noncontrolling membership interest redemption gain tax withholding (including $879 and $0 associated with variable interest entity for the three months ended March 31, 2025 and 2024, respectively)	(879)	0
Net cash used in financing activities	(10,370)	(8,544)
Net increase (decrease) in cash and cash equivalents	889	(9,932)
Cash and cash equivalents
Beginning of period	31,584	23,076
End of period	32,473	13,144
Supplemental disclosures of non-cash investing and financing activities:
Transfers from deposits to property and equipment	853	1,148
Non-cash purchases of property and equipment	37	159
Supplemental disclosures of cash flow information:
Income tax refund	0	13
Cash paid for interest	$ 477	$ 502