Finance Leases Receivable (Details)	3 Months Ended	9 Months Ended
	Sep. 30, 2018 USD ($) Aircraft	Sep. 30, 2018 USD ($) Aircraft	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Finance Leases Receivable [Abstract]
Number of aircraft with sales type finance leases | Aircraft	6	3
Number of aircraft sold | Aircraft	3
Cash proceeds from sale of aircraft	$ 1,088,700	$ 8,382,000	$ 2,980,000
Proceeds from sale of aircraft from maintenance reserves on one purchased aircraft	1,675,100
Proceeds from sale of aircraft from maintenance reserves from two leased aircraft	2,618,100
Net Investment Included in Finance Leases and Direct Financing Leases Receivable [Abstract]
Gross minimum lease payments receivable	18,160,700	18,160,700		$ 27,074,400
Less unearned interest	(2,105,200)	(2,105,200)		(3,513,400)
Finance leases receivable	16,055,500	16,055,500		$ 23,561,000
Minimum Future Payments Receivable under Finance Leases [Abstract]
Remainder of 2018	1,891,500	1,891,500
2019	4,047,600	4,047,600
2020	4,208,600	4,208,600
2021	4,805,000	4,805,000
2022	3,208,000	3,208,000
Total	$ 18,160,700	$ 18,160,700