Note 9 - Stock Option and Stock Plans - Stock Option Plan Summary (Details)	12 Months Ended
	Dec. 31, 2018 shares	[1]
2008 Stock Incentive Plan [Member]
Total Shares Authorized (in shares)	600,000
Shares Issued (in shares)	463,420
Shares Remaining (in shares)	136,580
2018 Employee Stock Option Plan [Member]
Total Shares Authorized (in shares)	6,000,000
Shares Issued (in shares)	950,000
Shares Remaining (in shares)	5,050,000
2018 Officers, Directors, Employees, and Consultants Nonqualified Stock Option Plan [Member]
Total Shares Authorized (in shares)	20,000,000
Shares Issued (in shares)	3,995,000
Shares Remaining (in shares)	16,005,000

[1] The Board of Directors has approved all stock, stock option and stock warrant issuances.