Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Current Assets
Cash and cash equivalents	$ 15,839	$ 33,333
Restricted cash	707	849
Marketable securities	136,562	153,827
Receivables, net	40,391	40,341
Notes receivable	21,093	19,452
Spare parts and supplies, net	5,029	4,579
Contract costs	108	143
Contract assets, net	1,618	0
Prepaid expenses and other	2,594	3,732
Total Current Assets	223,941	256,256
Property and Equipment
Flight property and equipment	265,636	263,970
Ground property and equipment	8,596	8,055
Less accumulated depreciation and amortization	(190,606)	(169,766)
Net Property and Equipment	83,626	102,259
Other Assets
Operating lease right-of-use asset	9,708	13,480
Intangibles	5,300	5,300
Long-term investments	4,275	4,275
Long-term contract costs	613	0
Other	969	1,077
Total Other Assets	20,865	24,132
Total Assets	328,432	382,647
Current Liabilities
Accounts payable	14,295	20,165
Accrued payroll and employee benefits	13,235	12,989
Current portion of operating lease liability	3,649	5,091
Other accrued expenses	166	137
Contract liabilities	0	1,985
Deferred revenues	0	16,561
Current portion of long-term debt (stated principal amount of $48,600 at September 30, 2023 and $3,500 at December 31, 2022)	52,554	9,154
Total Current Liabilities	83,899	66,082
Other Long-Term Liabilities
Long-term debt (stated principal amount of $0 at September 30, 2023 and $48,600 December 31, 2022)	0	52,068
Long-term promissory note	4,275	4,275
Deferred tax liability	4,424	7,990
Long-term operating lease liability	3,659	5,849
Long-term contract liabilities, net	2,792	0
Other	1,755	1,977
Total Long-Term Liabilities	16,905	72,159
Total Liabilities	100,804	138,241
Commitments and Contingencies (Note 8)
Mezzanine Equity (Note 10)
Series C Convertible Redeemable Preferred Stock, $0.01 par value per share, 4,000,000 shares authorized, issued and outstanding at September 30, 2023 and December 31, 2022	13,200	13,200
Stockholders’ Equity
Common Stock, $0.01 par value per share, 100,000,000 shares authorized, 55,481,140 shares issued at September 30, 2023 and December 31, 2022, 43,456,071 shares outstanding at September 30, 2023 and 45,219,737 shares outstanding at December 31, 2022	555	555
Additional paid-in capital	284,753	285,668
Retained deficit	(52,009)	(40,034)
Treasury stock	(18,871)	(14,983)
Total Stockholders’ Equity	214,428	231,206
Total Liabilities and Stockholders’ Equity	$ 328,432	$ 382,647