CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CURRENT ASSETS:
Cash and cash equivalents	$ 91,108	$ 132,275
Marketable securities	377,645	415,273
Restricted cash	11,582	11,582
Receivables, net	71,816	83,099
Inventories, net	139,316	137,452
Prepaid aircraft rents	444,328	397,850
Deferred tax assets	127,430	94,385
Other current assets	21,450	19,087
Total current assets	1,284,675	1,291,003
PROPERTY AND EQUIPMENT:
Aircraft and rotable spares	4,836,689	4,608,663
Deposits on aircraft	40,000	40,000
Buildings and ground equipment	272,819	274,900
Total property and equipment, gross	5,149,508	4,923,563
Less-accumulated depreciation and amortization	(1,930,108)	(1,902,375)
Total property and equipment, net	3,219,400	3,021,188
OTHER ASSETS
Intangible assets, net	12,186	12,748
Other assets	97,247	84,989
Total other assets	109,433	97,737
Total assets	4,613,508	4,409,928
CURRENT LIABILITIES:
Current maturities of long-term debt	232,460	211,821
Accounts payable	270,617	270,097
Accrued salaries, wages and benefits	133,699	138,902
Taxes other than income taxes	15,219	17,457
Other current liabilities	45,070	46,078
Total current liabilities	697,065	684,355
OTHER LONG-TERM LIABILITIES	48,825	49,625
LONG-TERM DEBT, net of current maturities	1,676,906	1,533,990
DEFERRED INCOME TAXES PAYABLE	710,317	669,385
DEFERRED AIRCRAFT CREDITS	69,841	72,227
COMMITMENTS AND CONTINGENCIES
STOCKHOLDERS' EQUITY:
Preferred stock, 5,000,000 shares authorized; none issued
Common stock, no par value, 120,000,000 shares authorized; 78,423,463 and 77,951,411 shares issued, respectively	628,875	626,521
Retained earnings	1,173,031	1,165,478
Treasury stock, at cost, 26,765,386 and 26,765,386 shares, respectively	(391,364)	(391,364)
Accumulated other comprehensive income (loss)	12	(289)
Total stockholders' equity	1,410,554	1,400,346
Total liabilities and stockholders' equity	$ 4,613,508	$ 4,409,928