Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2022	Sep. 30, 2021
Current assets:
Cash and cash equivalents	$ 54,448	$ 120,517
Restricted cash	3,348	3,350
Receivables, net	4,050	3,167
Expendable parts and supplies, net	26,341	24,467
Prepaid expenses and other current assets	7,234	6,885
Total current assets	95,421	158,386
Property and equipment, net	1,072,826	1,151,891
Intangible assets, net	6,026	6,792
Lease and equipment deposits	6,972	6,808
Operating lease right-of-use assets	65,878	93,100
Deferred heavy maintenance, net	6,848	3,499
Assets held for sale	36,528
Other assets	29,686	36,121
Total assets	1,320,185	1,456,597
Current liabilities:
Current portion of long-term debt and finance leases	112,776	111,710
Current portion of deferred revenue	726	6,298
Current maturities of operating leases	16,854	32,652
Accounts payable	66,811	61,476
Accrued compensation	10,781	12,399
Other accrued expenses	32,322	33,657
Total current liabilities	240,270	258,192
Noncurrent liabilities:
Long-term debt and finance leases, excluding current portion	523,231	539,700
Noncurrent operating lease liabilities	20,585	33,991
Deferred credits	3,295	3,934
Deferred income taxes	50,803	69,940
Deferred revenue, net of current portion	21,994	28,202
Other noncurrent liabilities	36,971	34,591
Total noncurrent liabilities	656,879	710,358
Total liabilities	897,149	968,550
Commitments and contingencies (Note 16)
Stockholders' equity:
Preferred stock of no par value, 5,000,000 shares authorized; no shares issued and outstanding
Common stock of no par value and additional paid-in capital, 125,000,000 shares authorized; 36,292,401 (2022) and 35,958,759 (2021) shares issued and outstanding, 4,899,497 (2022) and 4,899,497 (2021) warrants issued and outstanding	258,403	256,372
Retained earnings	164,633	231,675
Total stockholders' equity	423,036	488,047
Total liabilities and stockholders' equity	$ 1,320,185	$ 1,456,597