CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
OPERATING REVENUES:
Passenger	$ 745,411	$ 744,390
Ground handling and other	20,004	17,685
Total operating revenues	765,415	762,075
OPERATING EXPENSES:
Salaries, wages and benefits	300,039	305,557
Aircraft maintenance, materials and repairs	132,325	138,859
Depreciation and amortization	70,114	67,801
Aircraft rentals	57,709	67,124
Aircraft fuel	34,310	25,332
Ground handling services	19,535	20,984
Other operating expenses	75,088	74,609
Total operating expenses	689,120	700,266
OPERATING INCOME	76,295	61,809
OTHER INCOME (EXPENSE):
Interest income	660	430
Interest expense	(24,549)	(17,725)
Total other expense, net	(23,889)	(17,295)
INCOME BEFORE INCOME TAXES	52,406	44,514
PROVISION FOR INCOME TAXES	17,620	17,422
NET INCOME	$ 34,786	$ 27,092
BASIC EARNINGS PER SHARE (in dollars per share)	$ 0.67	$ 0.53
DILUTED EARNINGS PER SHARE (in dollars per share)	$ 0.65	$ 0.52
Weighted average common shares:
Basic (in shares)	51,820	51,218
Diluted (in shares)	53,202	52,014
COMPREHENSIVE INCOME:
Net income	$ 34,786	$ 27,092
Net unrealized appreciation on marketable securities, net of taxes	39	15
TOTAL COMPREHENSIVE INCOME	$ 34,825	$ 27,107