Note 11 - Stock Options - Summary of Expired Director Plans (Details)	12 Months Ended
	Sep. 30, 2017 $ / shares shares
Outstanding Stock Options (in shares) | shares	5,000
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 3.54
Number of Stock Options Exercisable (in shares) | shares	5,000
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 3.54
Exercise Price Range 1 [Member]
Outstanding Stock Options (in shares) | shares	4,000
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 2.925
Weighted Average Remaining Life (Year)	5 years 109 days
Number of Stock Options Exercisable (in shares) | shares	4,000
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 2.925
Range of Exercise Price, Lower Limit (in dollars per share)	$ 2.925
Exercise Price Range 2 [Member]
Outstanding Stock Options (in shares) | shares	1,000
Weighted Average Exercise Price, Outstanding (in dollars per share)	$ 6
Weighted Average Remaining Life (Year)	3 years 182 days
Number of Stock Options Exercisable (in shares) | shares	1,000
Weighted Average Exercise Price, Exercisable (in dollars per share)	$ 6
Range of Exercise Price, Upper Limit (in dollars per share)	$ 6