Variable Interest Entities (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) Aircraft Term_Loan Entity	Dec. 31, 2015 USD ($)
Variable Interest Entity [Line Items]
Borrowings from secured financings	$ 1,261,423	$ 1,146,238
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Number of Consolidated Variable Interest Entities | Entity	5
Number of Aircrafts | Aircraft	7
Air Knight VIEs | Variable Interest Entity, Primary Beneficiary | ECA Term Financings {Member]
Variable Interest Entity [Line Items]
Type of term loans | Term_Loan	7
Debt instrument, term	12 years
Net book value of flight equipment held for lease	$ 521,007
Consolidated debt outstanding	$ 306,103