CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
CURRENT ASSETS:
Cash and cash equivalents	$ 102,984	$ 258,421
Marketable securities	944,231	601,989
Receivables, net	100,523	65,348
Inventories, net	123,209	104,093
Other current assets	100,334	38,742
Total current assets	1,371,281	1,068,593
PROPERTY AND EQUIPMENT:
Aircraft and rotable spares	8,143,614	7,848,100
Deposits on aircraft	23,931	124,964
Buildings and ground equipment	265,019	256,595
Total property and equipment, gross	8,432,564	8,229,659
Less-accumulated depreciation and amortization	(2,884,084)	(2,731,060)
Total property and equipment, net	5,548,480	5,498,599
OTHER ASSETS:
Operating lease right-of-use assets	151,928	238,516
Long-term receivables and other assets	342,864	320,239
Total other assets	494,792	558,755
Total assets	7,414,553	7,125,947
CURRENT LIABILITIES:
Current maturities of long-term debt	438,502	391,798
Accounts payable	422,001	496,333
Accrued salaries, wages and benefits	186,285	150,583
Current maturities of operating lease liabilities	71,726	78,886
Taxes other than income taxes	20,480	28,869
Other current liabilities	33,549	48,152
Total current liabilities	1,172,543	1,194,621
LONG-TERM DEBT, net of current maturities	2,941,772	2,717,420
DEFERRED INCOME TAXES PAYABLE	687,060	663,236
NONCURRENT OPERATING LEASE LIABILITIES	88,622	158,274
OTHER LONG-TERM LIABILITIES	176,925	124,882
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; 82,592,830 and 82,335,970 shares issued as of December 31, 2022, and December 31, 2021, respectively	734,426	722,310
Retained earnings	2,236,869	2,163,916
Treasury stock, at cost, 31,994,416 and 31,956,047 shares as of December 31, 2022, and December 31, 2021, respectively	(619,862)	(618,712)
Accumulated other comprehensive loss	(3,802)
Total stockholders' equity	2,347,631	2,267,514
Total liabilities and stockholders' equity	$ 7,414,553	$ 7,125,947