Note 8 - Goodwill and Intangible Assets - Summary of Intangible Assets (Details) - USD ($)	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Sep. 30, 2019
Intangible assets, gross carrying amount	$ 1,752,105		$ 1,710,431
Accumulated amortization	(622,823)		(534,797)
Intangible assets, net	1,129,282		1,175,634
Amortization expense	74,562	$ 76,807
Technology-Based Intangible Assets [Member]
Intangible assets, gross carrying amount	626,587		611,043
Customer Relationships [Member]
Intangible assets, gross carrying amount	599,344		584,477
Trade Names [Member]
Intangible assets, gross carrying amount	217,943		212,537
Noncompete Agreements [Member]
Intangible assets, gross carrying amount	236,105		230,248
Patents [Member]
Intangible assets, gross carrying amount	$ 72,126		$ 72,126

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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