Note 9 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Reserves and accruals	$ 476,000	$ 204,000
Amortization	(11,000)	41,000
Capital losses and other	1,000	1,000
Non-qualified stock option expense	165,000	164,000
Loss Carryforwards	5,901,000	5,116,000
Total deferred tax assets	6,532,000	5,526,000
Valuation allowance	(3,081,000)	(1,500,000)
Net deferred tax assets	3,451,000	4,026,000
Depreciation	(3,451,000)	(4,026,000)
Total deferred tax liabilities	(3,451,000)	(4,026,000)
Net deferred tax assets (liabilities)