Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Cash Flows From Operating Activities:
Net income	$ 766,000	$ 8,107,000	$ 6,156,000	$ 19,668,000
Adjustments to reconcile net income to net cash provided by operating activities:
Stock-based compensation			238,000	274,000
Depreciation and amortization	209,000	186,000	611,000	546,000
Loss on marketable equity securities	0	24,000	0	42,000
Equity in income of unconsolidated affiliate	(112,000)	(250,000)	(623,000)	(456,000)
Operating lease expense, net of accretion			663,000	677,000
Changes in operating assets and liabilities:
Accounts receivable, net			4,141,000	(5,569,000)
Accounts receivable, related party			(491,000)	(109,000)
Inventories			(6,441,000)	(1,852,000)
Prepaid expenses			(337,000)	(1,272,000)
Accounts payable and accrued liabilities			(2,627,000)	2,540,000
Customer advance payments of orders			(209,000)	3,218,000
Lease liabilities			(660,000)	(669,000)
Net cash provided by operating activities			421,000	17,038,000
Cash Flows From Investing Activities:
Purchases of property and equipment			(2,391,000)	(687,000)
Proceeds from sales of marketable securities			0	120,000
Net cash used in investing activities			(2,391,000)	(567,000)
Cash Flows From Financing Activities:
Proceeds from exercise of stock options			391,000	1,970,000
Repurchase of common stock			(4,077,000)	(406,000)
Net cash provided by (used in) financing activities			(3,686,000)	1,564,000
Increase (decrease) in cash			(5,656,000)	18,035,000
Cash, beginning of the period			23,292,000	6,548,000
Cash, end of the period	$ 17,636,000	$ 24,583,000	$ 17,636,000	$ 24,583,000