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Carrying amount as of the balance sheet date of software licenses amount paid in advance which will be charged against earnings in periods after one year or beyond the operating cycle, if longer.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Supplemental Balance Sheet Disclosures - Property and Equipment (Details)	3 Months Ended		6 Months Ended
	Mar. 31, 2019 USD ($) aircraft	Mar. 31, 2018 USD ($) aircraft	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)
Property and equipment
Property and equipment, gross	$ 21,310,623		$ 21,310,623		$ 21,238,428
Less: accumulated depreciation and amortization	(12,670,091)		(12,670,091)		(12,451,691)
Property and equipment, net	8,640,532		8,640,532		8,786,737
Depreciation and amortization for property and equipment	111,000	$ 106,000	218,000	$ 209,000
Other assets
Intangible assets, net of accumulated amortization of $538,837 and $531,637 at December 31, 2018 and September 30, 2018, respectively	56,400		56,400		68,600
Other non-current assets	109,147		109,147		113,393
Total other assets	165,547		165,547		181,993
Accumulated amortization of intangible assets	543,837		543,837		531,637
Impairment charges			0	0
Intangible asset amortization expense	5,000	$ 0	12,000	0
Prepaid software licenses	34,000		34,000		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	2,291,809		2,291,809		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	$ 2,000	$ 2,000	$ 4,000	$ 2,000