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Long-Term Debt (Details)			1 Months Ended			3 Months Ended		6 Months Ended	60 Months Ended
	Apr. 20, 2020	Feb. 13, 2020 USD ($)	Jul. 31, 2020 USD ($)	Apr. 30, 2020 Aircraft	Feb. 28, 2019 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2018 USD ($)	Jun. 30, 2020 USD ($) Aircraft	Apr. 30, 2030	Apr. 30, 2025	Apr. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)	Mar. 31, 2019 USD ($)	Feb. 01, 2019 USD ($)
Debt Instrument, Term				8 years
Line of Credit Facility, Maximum Borrowing Capacity													$ 175,000,000.0
Line of Credit Facility, Fair Value of Amount Outstanding						$ 0		$ 0				$ 81,000,000.0
Number of Terms to be Included in the Collateral Pool							2 years
Number Of Aircrafts Included As Collateral | Aircraft				2
Debt Instrument, Face Amount		$ 545,500,000									$ 31,000,000.0			$ 450,000,000.0
Debt Instrument, Increase (Decrease), Net		$ 100,000,000.0
Debt Instrument, Periodic Payment, Principal					$ 1,400,000
Termination Loans						19,800,000		$ 19,800,000
Senior Secured Revolving Credit Facility
Debt Instrument, Term							24 months
Line of Credit Facility, Maximum Borrowing Capacity							$ 81,000,000.0
Number Of Aircrafts Included As Collateral | Aircraft								8
Long-term Debt [Member]
reduction in debt interest rate		150.00%
Payroll Support Program Loan CARES Act [Member] | Unsecured Debt [Member]
Debt Instrument, Term	10 years			10 years
Debt Instrument, Interest Rate, Stated Percentage	1.00%
Proceeds From Payroll Support Program, Low-Interest Loan						$ 16,400,000		$ 21,600,000
Subsequent Event | Payroll Support Program Loan CARES Act [Member] | Unsecured Debt [Member]
Debt Instrument, Interest Rate Terms										P5Y
Proceeds From Payroll Support Program, Low-Interest Loan			$ 5,200,000
Subsequent Event | Forecast [Member] | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate [Member] | Payroll Support Program Loan CARES Act [Member] | Unsecured Debt [Member]
Debt Instrument, Basis Spread on Variable Rate									2.00%

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