Note 10 - Leases - Operating Lease Expense (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Total lease expense under ASC 842	$ 307,794	$ 274,272	$ 616,128	$ 516,266
Cost of Sales [Member]
Total lease expense under ASC 842	252,459	218,874	505,395	404,502
Selling, General and Administrative Expenses [Member]
Total lease expense under ASC 842	$ 55,335	$ 55,398	$ 110,733	$ 111,764