Statements Of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating revenues:
Passenger	$ 1,169,338	$ 1,144,972	$ 986,018
Non-ticket	972,125	786,608	668,367
Total operating revenues	2,141,463	1,931,580	1,654,385
Operating expenses:
Aircraft fuel	461,447	612,909	551,746
Salaries, wages and benefits	378,210	313,988	262,150
Aircraft rent	211,531	195,827	169,737
Landing fees and other rents	131,077	105,115	83,604
Distribution	86,576	74,823	67,481
Maintenance, materials and repairs	80,448	73,956	60,143
Depreciation and amortization	73,908	46,971	31,947
Other operating	206,867	149,675	144,586
Loss on disposal of assets	1,604	3,008	525
Special charges	673	45	174
Total operating expenses	1,632,341	1,576,317	1,372,093
Operating income	509,122	355,263	282,292
Other (income) expense:
Interest expense	20,382	2,747	214
Capitalized interest	(11,553)	(2,747)	(214)
Interest income	(2,125)	(336)	(401)
Other expense	15	2,605	283
Total other (income) expense	6,719	2,269	(118)
Income before income taxes	502,403	352,994	282,410
Provision for income taxes	185,183	127,530	105,492
Net income	$ 317,220	$ 225,464	$ 176,918
Basic earnings per share (in dollars per share)	$ 4.39	$ 3.10	$ 2.44
Diluted earnings per share (in dollars per share)	$ 4.38	$ 3.08	$ 2.42