Note 2 - Revenue Recognition (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Revenue from Contract with Customer, Including Assessed Tax	$ 12,021,820	$ 17,559,315	$ 37,943,303	$ 37,259,352
Wireless Services [Member]
Contract with Customer, Liability, Revenue Recognized	500,000
Customer Concentration Risk [Member] | Revenue Benchmark [Member] | Largest Customer [Member]
Concentration Risk, Percentage			14.00%
International Regions Excluding Central America and South America [Member]
Revenue from Contract with Customer, Including Assessed Tax	700,000	$ 600,000	$ 1,500,000	$ 1,600,000
Contract with Customer, Asset, after Allowance for Credit Loss, Total	700,000		700,000		$ 2,700,000
Contract with Customer, Liability, Total	$ 200,000		200,000		$ 100,000
Contract with Customer, Liability, Revenue Recognized			$ 100,000