Condensed Statements Of Operations (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Operating revenues:
Passenger	$ 356,207	$ 331,004	$ 1,027,891	$ 900,031
Non-ticket	331,024	290,325	952,768	843,574
Total operating revenues	687,231	621,329	1,980,659	1,743,605
Operating expenses:
Salaries, wages and benefits	134,114	120,190	391,144	349,530
Aircraft fuel	158,300	121,844	440,376	321,018
Aircraft rent	53,396	49,367	163,032	151,433
Landing fees and other rents	48,498	39,345	134,538	114,096
Depreciation and amortization	36,840	25,304	103,680	73,370
Maintenance, materials and repairs	26,176	30,443	81,473	72,010
Distribution	29,469	25,565	85,875	73,190
Special charges	7,853	7,355	12,629	31,609
Loss on disposal of assets	516	423	3,114	1,166
Other operating	87,965	66,277	268,553	197,833
Total operating expenses	583,127	486,113	1,684,414	1,385,255
Operating income	104,104	135,216	296,245	358,350
Other (income) expense:
Interest expense	15,018	11,362	41,237	29,588
Capitalized interest	(3,203)	(3,067)	(10,125)	(9,163)
Interest income	(2,605)	(1,222)	(5,746)	(4,235)
Other expense	114	180	221	407
Total other (income) expense	9,324	7,253	25,587	16,597
Income before income taxes	94,780	127,963	270,658	341,753
Provision for income taxes	34,590	46,581	100,390	125,367
Net income	$ 60,190	$ 81,382	$ 170,268	$ 216,386
Basic earnings per share (in dollars per share)	$ 0.87	$ 1.17	$ 2.45	$ 3.06
Diluted earnings per share (in dollars per share)	$ 0.87	$ 1.17	$ 2.45	$ 3.05