Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	3 Months Ended
	Mar. 31, 2019		Mar. 31, 2018
Cash Flows From Operating Activities:
Net income	$ 1,218,000		$ 508,000
Adjustments to reconcile net income to net cash used in operating activities:
Stock-based compensation	122,000		78,000
Depreciation and amortization	127,000		146,000
Gain on marketable securities	(170,000)		(32,000)
Equity in income of unconsolidated affiliate	(277,000)		(139,000)
Operating lease expense, net of accretion	164,000
Changes in assets and liabilities:
Accounts receivable, net	(2,267,000)		(1,866,000)
Accounts receivable, related party	(454,000)		(20,000)
Inventories	(529,000)		(386,000)
Prepaid expenses	1,302,000		(790,000)
Accounts payable and accrued liabilities	(505,000)		5,000
Lease liabilities	(160,000)
Net cash used in operating activities	(1,429,000)		(2,496,000)
Cash Flows From Investing Activities:
Purchase of property and equipment	(152,000)		(102,000)
Proceeds from sales of marketable securities	10,000
Net cash used in investing activities	(142,000)		(102,000)
Cash Flows From Financing Activities:
Proceeds from exercise of stock options	60,000		77,000
Repurchase of common stock	(1,008,000)		(576,000)
Net cash used in financing activities	(948,000)		(499,000)
Decrease in cash	(2,519,000)		(3,097,000)
Cash, beginning of the period	7,007,000	[1]	8,763,000
Cash, end of the period	$ 4,488,000		$ 5,666,000

[1] The condensed consolidated balance sheet as of December 31, 2018 has been prepared using information from the audited consolidated balance sheet as of that date.