Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating revenues:
Passenger	$ 1,144,972	$ 986,018	$ 782,792
Non-ticket	786,608	668,367	535,596
Total operating revenues	1,931,580	1,654,385	1,318,388
Operating expenses:
Aircraft fuel	612,909	551,746	471,763
Salaries, wages and benefits	313,988	262,150	218,919
Aircraft rent	195,827	169,737	143,572
Landing fees and other rents	105,115	83,604	68,368
Distribution	74,823	67,481	56,668
Maintenance, materials and repairs	73,956	60,143	49,460
Depreciation and amortization	46,971	31,947	15,256
Other operating	149,675	144,586	127,886
Loss on disposal of assets	3,008	525	956
Special charges (credits)	45	174	(8,450)
Total operating expenses	1,576,317	1,372,093	1,144,398
Operating income	355,263	282,292	173,990
Other (income) expense:
Interest expense	2,747	214	1,350
Capitalized interest	(2,747)	(214)	(1,350)
Interest income	(336)	(401)	(925)
Other expense	2,605	283	331
Total other (income) expense	2,269	(118)	(594)
Income before income taxes	352,994	282,410	174,584
Provision for income taxes	127,530	105,492	66,124
Net income	$ 225,464	$ 176,918	$ 108,460
Basic earnings per share (in dollars per share)	$ 3.10	$ 2.44	$ 1.50
Diluted earnings per share (in dollars per share)	$ 3.08	$ 2.42	$ 1.49