Lease Rental Revenues and Flight Equipment Held for Lease (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) Aircraft Lessee	Dec. 31, 2018 USD ($) Aircraft Lessee	Dec. 31, 2017 Lessee
Revenue, Major Customer [Line Items]
Net Book Value | $	$ 7,375,018	$ 6,935,585
Maintenance Payments
Revenue, Major Customer [Line Items]
Lease incentive, payable | $	$ 9,176	$ 15,636
Lease Revenue | Customer Concentration Risk | Major Customer Group One
Revenue, Major Customer [Line Items]
Concentration Risk, Number of Customers in Major Customer Group | Lessee	2	3	4
Percentage of geographic concentration	16.00%	18.00%	24.00%
B-777-300 [Member]
Revenue, Major Customer [Line Items]
Offlease Aircraft with Future Lease Commitments		1
A-330-200 [Member]
Revenue, Major Customer [Line Items]
Offlease Aircraft with Future Lease Commitments	1	1
B-737-800 [Member]
Revenue, Major Customer [Line Items]
Number of Offlease Aircraft Marketed for Lease	1
Offlease Aircraft with Future Lease Commitments		1
A-320-200 [Member]
Revenue, Major Customer [Line Items]
Offlease Aircraft with Future Lease Commitments	1	10
Number of Offlease Aircraft Sold		1