Summary of Significant Accounting Policies - Schedule of Property and Equipment Useful lives (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Aircraft [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Useful Life	7 years
Current Residual Value	$ 50,000
Rotable Parts [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Useful Life	7 years
Current Residual Value, percent	10.00%
Spare Engines [Member]
Property, Plant and Equipment [Line Items]
Property Plant And Equipment Useful Life	7 years
Current Residual Value	$ 25,000
Ground Equipment [Member]
Property, Plant and Equipment [Line Items]
Current Residual Value, percent	0.00%
Property Plant And Equipment Useful Life	Up to 10 years
Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Current Residual Value, percent	0.00%
Property Plant And Equipment Useful Life	Up to 10 years
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Current Residual Value, percent	0.00%
Property Plant And Equipment Useful Life	Shorter of asset or lease life