CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($)	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net income	$ 29,003,000	$ 21,296,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization (including $910 associated with variable interest entity for both the nine months ended September 30, 2023 and 2022)	8,058,000	7,752,000
Adjustments to allowance for doubtful accounts	(673,000)	1,112,000
Adjustments to inventory reserve	(27,000)	441,000
Write-off of inventory	3,225,000	0
Impairment of deposits	523,000	0
Loss (gain), net, on disposal of machinery and equipment	1,708,000	(33,000)
Change in fair value of interest rate swap (including $0 and $2,159 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	0	(2,159,000)
Amortization of loan fees (including $41 and $28 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	57,000	28,000
Accrued interest on certificates of deposit	(63,000)	0
Stock-based compensation	743,000	1,774,000
Amortization of operating right-of-use assets	3,617,000	2,897,000
(Increase) decrease in operating assets
Accounts receivable (including $6 and $21 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(3,399,000)	(5,068,000)
Inventories	(3,649,000)	(15,255,000)
Prepaid expenses and other current assets (including $22 and $396 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	431,000	(2,264,000)
Other assets (including $34 and $458 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(75,000)	(43,000)
Increase (decrease) in operating liabilities
Accounts payable (including $57 and $470 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	1,701,000	459,000
Accrued expenses (including $163 and $414 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(147,000)	1,130,000
Related party payable	(2,385,000)	2,855,000
Income taxes payable	8,010,000	111,000
Customer deposits (including $49 and $156 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(478,000)	(29,000)
Operating lease liability	(3,313,000)	(2,897,000)
Other liabilities (including $0 and $1 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	172,000	150,000
Other payables	49,000	242,000
Net cash provided by operating activities	43,088,000	12,499,000
Cash flows from investing activities
Purchases of property and equipment	(2,870,000)	(2,007,000)
Proceeds from disposal of property and equipment	605,000	76,000
Payments for costs incurred from sale of machinery and equipment	(189,000)	0
Deposits paid for joint venture investment	(2,900,000)	(4,000,000)
Deposits refunded from joint venture investment	6,900,000	0
Deposit refund from cancelled property and equipment purchase	503,000	0
Deposits paid for property and equipment	(5,390,000)	(11,471,000)
Proceeds from settlement of interest rate swap (including $0 and $825 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	0	825,000
Purchase of short-term investments (including $8,000 and $0 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(28,000,000)	0
Redemption of short-term investments	10,000,000	0
Net cash used in investing activities	(21,341,000)	(16,577,000)
Cash flows from financing activities
Proceeds from line of credit	0	21,100,000
Payments on line of credit	0	(21,100,000)
Proceeds from long-term debt (including $8,000 and $27,477 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	8,000,000	27,477,000
Payments for lender fees	(61,000)	0
Payments on long-term debt (including $733 and $21,338 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	(733,000)	(21,338,000)
Tax withholding on vesting of restricted stock units	(18,000)	0
Proceeds from exercise of common stock options	103,000	51,000
Dividends paid to shareholders	(16,917,000)	0
Payments of noncontrolling interest tax withholding (including $0 and $1,064 associated with variable interest entity for the nine months ended September 30, 2023 and 2022, respectively)	0	(1,064,000)
Net cash (used in) provided by financing activities	(9,626,000)	5,126,000
Net increase in cash and cash equivalents	12,121,000	1,048,000
Cash and cash equivalents
Beginning of period	16,041,000	6,483,000
End of period	28,162,000	7,531,000
Supplemental disclosures of non-cash investing and financing activities:
Transfers from deposit to property and equipment	8,953,000	6,639,000
Non-cash purchases of property and equipment	71,000	0
Supplemental disclosures of cash flow information:
Cash paid for income tax	309,000	7,069,000
Cash paid for interest	$ 1,493,000	$ 1,541,000