Note 8 - Stockholders' Equity (Details Textual) - USD ($)					1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	May 01, 2014	Jan. 02, 2014	Sep. 15, 2003	Apr. 29, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2008	Dec. 31, 2020
Stock Issued During Period, Shares, Warrant Exercises (in shares)	187,296	187,296
Treasury Stock, Shares, Acquired (in shares)				745,536
Treasury Stock Acquired, Average Cost Per Share (in dollars per share)				$ 0.70
Treasury Stock, Value, Acquired, Cost Method				$ 521,875						$ 699
Treasury Stock, Acquired, Percentage Outstanding Shares				50.11%
Preferred Stock, Shares Authorized (in shares)						5,000,000		5,000,000			5,000,000
Preferred Stock, Shares Issued, Total (in shares)						0		0			0
Share-based Payment Arrangement, Expense						$ 62,209	$ 0	$ 104,809	$ 0
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in shares)					175,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)					$ 1.99
Share-based Compensation Arrangement by Share-based Payment Award, Illiquidity Discount					15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)					3 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period (Year)					7 years
Share-based Payment Arrangement, Expense						$ 62,209
Purchase Agreement [Member]
Stock Issued During Period, Shares, New Issues (in shares)			131,429
Stock Issued During Period, Percentage Outstanding			7.00%
Stock Issued During Period, Value, New Issues			$ 230,000