Condensed Statements Of Operations (unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Operating revenues:
Passenger	$ 241,119	$ 211,812	$ 460,016	$ 391,890
Non-ticket	166,220	134,496	317,760	255,913
Total operating revenue	407,339	346,308	777,776	647,803
Operating expenses:
Aircraft fuel	135,251	120,233	266,917	228,958
Salaries, wages and benefits	64,456	53,489	125,953	106,143
Aircraft rent	41,915	36,060	82,987	68,933
Landing fees and other rents	21,346	17,066	39,402	32,180
Distribution	17,277	14,738	32,958	28,939
Maintenance, materials and repairs	15,202	13,115	26,982	23,043
Depreciation and amortization	7,604	3,327	13,928	6,197
Other operating	37,416	33,100	71,915	60,609
Loss on disposal of assets	91	33	261	482
Special charges (credits)	23	15	46	(57)
Total operating expenses	340,581	291,176	661,349	555,427
Operating income	66,758	55,132	116,427	92,376
Other (income) expense:
Interest expense	95	794	104	1,334
Capitalized interest	(95)	(794)	(104)	(1,334)
Interest income	(105)	(180)	(221)	(595)
Other expense	36	84	137	127
Total other (income) expense	(69)	(96)	(84)	(468)
Income before income taxes	66,827	55,228	116,511	92,844
Provision for income taxes	24,759	20,637	43,889	34,834
Net income	$ 42,068	$ 34,591	$ 72,622	$ 58,010
Basic earnings per share	$ 0.58	$ 0.48	$ 1.00	$ 0.80
Diluted earnings per share	$ 0.58	$ 0.48	$ 1.00	$ 0.80