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Note 1 - Description of Business (Details Textual) - USD ($)			12 Months Ended
	Aug. 09, 2017	Aug. 03, 2017	Dec. 31, 2018	Dec. 31, 2017	Feb. 28, 2019	Feb. 07, 2019	Feb. 08, 2018	Mar. 02, 2017	Feb. 09, 2017	Dec. 31, 2016
Cash and Cash Equivalents, at Carrying Value, Ending Balance			$ 1,652,000	$ 224,000						$ 64,000
Net Income (Loss) Attributable to Parent, Total			2,287,000	(30,000)
Other Nonoperating Income				928,000
Proceeds from Sale of Short-term Investments		$ 56,000		56,000
Revolving Credit Facility [Member] \| Chief Executive Officer [Member]
Line of Credit Facility, Maximum Borrowing Capacity							$ 3,700,000	$ 3,700,000	$ 3,400,000
Revolving Credit Facility [Member] \| Chief Executive Officer [Member] \| Subsequent Event [Member]
Line of Credit Facility, Current Borrowing Capacity					$ 885,000
Line of Credit Facility, Maximum Borrowing Capacity					$ 2,700,000	$ 2,700,000
IP Addresses [Member]
Proceeds from Sale of Intangible Assets	$ 872,000			$ 872,000