CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 307,909	$ 328,384
Marketable Securities	263,597	360,945
Income tax receivable	24,478	25,936
Receivables, net	77,532	64,194
Inventories, net	111,941	127,690
Prepaid aircraft rents		87,031
Other current assets	24,932	26,614
Total current assets	810,389	1,020,794
PROPERTY AND EQUIPMENT:
Aircraft and rotable spares	6,903,732	6,433,916
Deposits on aircraft	50,906	42,012
Buildings and ground equipment	248,405	291,544
Total property and equipment, gross	7,203,043	6,767,472
Less-accumulated depreciation and amortization	(1,906,345)	(1,761,728)
Total property and equipment, net	5,296,698	5,005,744
OTHER ASSETS:
Operating lease right-of-use assets	326,700
Long-term prepaid assets		181,830
Other assets	163,872	104,844
Total other assets	490,572	286,674
Total assets	6,597,659	6,313,212
CURRENT LIABILITIES:
Current maturities of long-term debt	362,582	350,206
Accounts payable	328,854	331,982
Accrued salaries, wages and benefits	129,507	161,606
Current maturities of operating lease liabilities	87,472
Taxes other than income taxes	18,708	16,024
Other current liabilities	34,416	65,008
Total current liabilities	961,539	924,826
LONG-TERM DEBT, net of current maturities	2,622,236	2,809,768
DEFERRED INCOME TAXES PAYABLE	596,897	518,159
DEFERRED AIRCRAFT CREDITS		29,308
NONCURRENT OPERATING LEASE LIABILITIES	254,258
OTHER LONG-TERM LIABILITIES	46,469	66,870
COMMITMENTS AND CONTINGENCIES (Note 6)
STOCKHOLDERS' EQUITY:
Preferred stock, 5,000,000 shares authorized; none issued
Common stock, no par value, 120,000,000 shares authorized; 81,742,904 and 81,239,289 shares issued, respectively	684,541	690,910
Retained earnings	2,012,691	1,776,585
Treasury stock, at cost, 31,252,786 and 29,850,999 shares, respectively	(580,972)	(503,182)
Accumulated other comprehensive loss		(32)
Total stockholders' equity	2,116,260	1,964,281
Total liabilities and stockholders' equity	$ 6,597,659	$ 6,313,212