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Supplemental Balance Sheet Disclosures - Property and Equipment (Details)	3 Months Ended		9 Months Ended
	Jun. 30, 2019 USD ($) aircraft	Jun. 30, 2018 USD ($) aircraft	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Sep. 30, 2018 USD ($)
Property and equipment
Property and equipment, gross	$ 21,303,966		$ 21,303,966		$ 21,238,428
Less: accumulated depreciation and amortization	(12,762,168)		(12,762,168)		(12,451,691)
Property and equipment, net	8,541,798		8,541,798		8,786,737
Depreciation and amortization for property and equipment	103,000	$ 105,000	321,000	$ 314,000
Other assets
Intangible assets, net of accumulated amortization of $546,237 and $531,637 at June 30, 2019 and September 30, 2018, respectively	54,000		54,000		68,600
Other non-current assets	106,157		106,157		113,393
Total other assets	160,157		160,157		181,993
Accumulated amortization of intangible assets	546,237		546,237		531,637
Impairment charges			0	0
Intangible asset amortization expense	3,000	$ 0	15,000	0
Prepaid software licenses	31,000		31,000		38,000
Land
Property and equipment
Property and equipment, gross	1,021,245		1,021,245		1,021,245
Computer equipment
Property and equipment
Property and equipment, gross	2,285,152		2,285,152		2,268,969
Corporate airplanes
Property and equipment
Property and equipment, gross	$ 5,601,039		5,601,039		5,601,039
Number of airplanes depreciated \| aircraft		2
Pilatus PC-12
Property and equipment
Number of airplanes depreciated \| aircraft	1
Furniture and office equipment
Property and equipment
Property and equipment, gross	$ 1,033,779		1,033,779		1,033,779
Manufacturing facility
Property and equipment
Property and equipment, gross	5,733,313		5,733,313		5,733,313
Equipment
Property and equipment
Property and equipment, gross	5,629,438		5,629,438		$ 5,580,083
Prepaid software licenses
Other assets
Intangible asset amortization expense	$ 3,000	$ 2,000	$ 7,000	$ 3,000