CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
CURRENT ASSETS:
Cash and cash equivalents	$ 125,330	$ 102,984
Marketable securities	694,171	944,231
Receivables, net	118,844	100,523
Inventories, net	127,129	123,209
Other current assets	96,522	100,334
Total current assets	1,161,996	1,371,281
PROPERTY AND EQUIPMENT:
Aircraft and rotable spares	8,254,591	8,143,614
Deposits on aircraft	79,459	23,931
Buildings and ground equipment	285,924	265,019
Total property and equipment, gross	8,619,974	8,432,564
Less-accumulated depreciation and amortization	(3,121,549)	(2,884,084)
Total property and equipment, net	5,498,425	5,548,480
OTHER ASSETS:
Operating lease right-of-use assets	85,746	151,928
Long-term receivables and other assets	312,951	342,864
Total other assets	398,697	494,792
Total assets	7,059,118	7,414,553
CURRENT LIABILITIES:
Current maturities of long-term debt	443,186	438,502
Accounts payable	486,731	422,001
Accrued salaries, wages and benefits	189,510	186,285
Current maturities of operating lease liabilities	19,225	71,726
Taxes other than income taxes	24,736	20,480
Other current liabilities	42,282	33,549
Total current liabilities	1,205,670	1,172,543
LONG-TERM DEBT, net of current maturities	2,633,707	2,941,772
DEFERRED INCOME TAXES PAYABLE	681,575	687,060
NONCURRENT OPERATING LEASE LIABILITIES	66,520	88,622
OTHER LONG-TERM LIABILITIES	334,948	176,925
COMMITMENTS AND CONTINGENCIES (Note 7)
STOCKHOLDERS' EQUITY:
Preferred stock, 5,000,000 shares authorized; none issued
Common stock, no par value, 120,000,000 shares authorized; 82,840,372 and 82,592,830 shares issued as of September 30, 2023, and December 31, 2022, respectively	750,133	734,426
Retained earnings	2,253,695	2,236,869
Treasury stock, at cost, 41,619,716 and 31,994,416 shares as of September 30, 2023, and December 31, 2022, respectively	(866,946)	(619,862)
Accumulated other comprehensive loss	(184)	(3,802)
Total stockholders' equity	2,136,698	2,347,631
Total liabilities and stockholders' equity	$ 7,059,118	$ 7,414,553