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DEBT - Long-term Debt schedule (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Oct. 26, 2020
DEBT
Total Debt	$ 280,931	$ 285,801
Less: Unamortized debt issuance costs	(3,505)	(3,338)
Less: Current Maturities of Long-term Debt	(29,412)	(26,118)
Total Long-term Debt	248,014	256,345
Notes payable under the Company's 2019-1 EETC agreement
DEBT
Total Debt	202,984	227,347
Face amount	$ 248,587	$ 248,587
Weighted average interest rate	4.76%
Notes payable under the Company's 2019-1 EETC agreement \| Minimum
DEBT
Interest Rate	4.13%	4.13%
Notes payable under the Company's 2019-1 EETC agreement \| Maximum
DEBT
Interest Rate	6.95%	6.95%
Delayed Draw Term Loan Facility
DEBT
Total Debt	$ 77,481
U. S. Department of the Treasury CARES Act Loan
DEBT
Total Debt		$ 45,419
Face amount			$ 45,000
Notes payable to Wilmington Trust Company
DEBT
Total Debt		$ 12,506
Interest Rate		8.45%
Other Notes payable
DEBT
Total Debt	$ 466	$ 529
Interest Rate	5.00%	5.00%