Note 17 - Segment Information - Segment Disclosures (Details) - USD ($)	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Revenues	$ 26,306,790	$ 20,314,178
Revenues	(26,306,790)	(20,314,178)
Operating Income	(1,476,465)	(807,740)
Depreciation and amortization	483,087	153,283
Interest expense	20,949
Income tax expense	2,375,600	197,600
Long-lived assets	6,452,061	565,292
Total assets	41,860,797	38,857,800
Intersegment Eliminations [Member]
Revenues	(313,110)
Revenues	313,110
LRAD Segment [Member]
Revenues	24,836,795	20,314,178
Revenues	(24,836,795)	(20,314,178)
Operating Income	(1,387,902)	(807,740)
Depreciation and amortization	254,618	153,283
Interest expense
Income tax expense	2,375,600	197,600
Long-lived assets	2,478,144	565,292
Total assets	36,770,872	38,857,800
LRAD Segment [Member] | Intersegment Eliminations [Member]
Revenues
Revenues
Genasys Segment [Member]
Revenues	1,469,995
Revenues	(1,469,995)
Operating Income	(88,563)
Depreciation and amortization	228,469
Interest expense	20,949
Income tax expense
Long-lived assets	3,973,917
Total assets	5,089,925
Genasys Segment [Member] | Intersegment Eliminations [Member]
Revenues	(313,110)
Revenues	$ 313,110