Goodwill and Other Intangibles (Schedule Intangible Assets) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Finite and Indefinite-lived Intangible Assets by Major Class [Line Items]
Incentive to Lessee	$ 108,712	$ 126,007
Amortization of Lease Incentives	(17,295)
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Carrying value at beginning of period	111,316
Carrying value at beginning of period	120,316
Amortization expense	(7,933)
Carrying value at end of period	103,383	$ 111,316
Carrying value at end of period	112,383
ACMI Services [Member] | Airline Certificates [Member]
Finite and Indefinite-lived Intangible Assets [Roll Forward]
Carrying value at beginning of period	9,000
Amortization expense	0
Carrying value at end of period	$ 9,000