Fair Value Measurements Fair Value Measurements (Details 4) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of aircraft		$ 28,585	$ 119,835	$ 93,993
Maintenance Revenue		33,590	71,049	88,006
Other Revenue, Net		$ 7,311	$ 17,742	$ 11,208
Transactional
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impairment of aircraft	$ 23,955
Maintenance Revenue	$ 18,234