Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Cash Flows From Operating Activities:
Net income	$ 6,220,000	$ 1,010,000	$ 11,561,000	$ 2,228,000
Adjustments to reconcile net income to net cash used in operating activities:
Stock-based compensation			183,000	260,000
Depreciation and amortization	178,000	140,000	360,000	267,000
Loss (gain) on marketable securities	(41,000)	(439,000)	18,000	(609,000)
Equity in income of unconsolidated affiliate	(119,000)	(84,000)	(206,000)	(361,000)
Operating lease expense, net of accretion			450,000	366,000
Changes in assets and liabilities:
Accounts receivable, net			(3,093,000)	(250,000)
Accounts receivable, related party			(228,000)	(454,000)
Inventories			(677,000)	(991,000)
Prepaid expenses			(523,000)	589,000
Accounts payable and accrued liabilities			2,872,000	(525,000)
Customer advance payments of orders			6,475,000
Lease liabilities			(443,000)	(327,000)
Net cash provided by operating activities			16,749,000	193,000
Cash Flows From Investing Activities:
Purchase of property and equipment			(419,000)	(254,000)
Proceeds from sales of marketable securities			47,000	133,000
Net cash used in investing activities			(372,000)	(121,000)
Cash Flows From Financing Activities:
Proceeds from exercise of stock options			1,935,000	59,000
Repurchase of common stock			(125,000)	(1,636,000)
Net cash provided (used) in financing activities			1,810,000	(1,577,000)
Increase (decrease) in cash			18,187,000	(1,505,000)
Cash, beginning of the period			6,548,000	7,007,000
Cash, end of the period	$ 24,735,000	$ 5,502,000	$ 24,735,000	$ 5,502,000