Loss on Disposal of Assets - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) aircraft	Dec. 31, 2019 USD ($) aircraft	Dec. 31, 2018 USD ($) aircraft_Engine
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on disposal of assets	$ 2,264	$ 17,350	$ 9,580
Capitalized costs for enterprise accounting software write-off	1,500	2,400
Inventory write-down	$ 800	13,400	$ 4,400
Impairment of long-lived assets to be disposed of		3,100
Gain on sale-leaseback transaction		$ 1,500
Number of engines sold | aircraft_Engine			6
2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of sale and leaseback transactions | aircraft	1
2019
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of sale and leaseback transactions | aircraft		6
V2500 SelectOne Engine
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from the sale of used engines			$ 11,400
Loss on sale of used engines			$ 5,200