Organization and Summary of Significant Accounting Policies, Finance Leases (Details)	12 Months Ended
	Dec. 31, 2018 USD ($) Aircraft Lease	Dec. 31, 2017 USD ($)
Finance Leases [Abstract]
Number of aircraft with sales type finance leases	3
Number of aircraft with direct financing leases	3
Number of finance leases | Lease	6
Interest earned on finance lease | $	$ 1,251,000	$ 1,571,500