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Summary of Significant Accounting Policies (Details)			3 Months Ended		9 Months Ended		12 Months Ended
Summary of Significant Accounting Policies (Details)	Jan. 01, 2018	Dec. 31, 2017	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) segment	Jun. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)
Number of business segments
Number of business segments in which the entity operates \| segment					1
Long-Lived Assets
Impairment charges					$ 0	$ 0
Income Taxes
U.S. Federal statutory tax rate (as a percent)	21.00%	35.00%					24.50%
Net operating losses (as a percent)					80.00%
Deferred income tax expense								$ 321,038
Engineering Development
Percentage of employees who were engineers engaged in various engineering development projects					22.00%
Warranty
Length of warranty period					24 months
Contract Balances
Balance at beginning of the period					$ 356,801
Contract asset additions					30,170	(440,943)
Performance obligations satisfied during the period that were included in the contract liability balance at the beginning of the period					(267,316)
Increases due to invoicing prior to satisfaction of performance obligations					93,526
Balance at end of the period (contract assets)			$ 30,170		30,170
Balance at end of the period			183,011		183,011		$ 356,801
Customer Service Revenue
Customer Service Sales			4,589,824	$ 3,389,663	12,770,601	10,204,851
Customer Service Cost of Sales			2,064,617	1,806,980	5,733,385	5,482,596
Gross profit			2,525,207	1,582,683	7,037,216	4,722,255
Customer Service
Customer Service Revenue
Customer Service Sales			1,059,528	1,000,436	2,535,576	3,224,743
Customer Service Cost of Sales			353,348	463,513	982,313	1,465,091
Gross profit			$ 706,180	$ 536,923	$ 1,553,263	$ 1,759,652
Property and equipment except manufacturing facility and the corporate airplane \| Minimum
Number of business segments
Estimated useful lives					3 years
Property and equipment except manufacturing facility and the corporate airplane \| Maximum
Number of business segments
Estimated useful lives					7 years
Manufacturing facility
Number of business segments
Estimated useful lives					39 years
Corporate airplanes
Number of business segments
Estimated useful lives					10 years