CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
OPERATING REVENUES:
Passenger	$ 3,467,546	$ 3,584,777	$ 2,724,276
Ground handling and other	66,826	70,146	40,869
Total operating revenues	3,534,372	3,654,923	2,765,145
OPERATING EXPENSES:
Salaries, wages and benefits	1,171,689	1,155,051	764,933
Aircraft maintenance, materials and repairs	659,869	712,926	487,466
Aircraft fuel	426,387	592,871	340,074
Aircraft rentals	333,637	346,526	311,909
Depreciation and amortization	251,958	254,182	236,499
Station rentals and landing fees	169,855	174,838	129,537
Ground handling services	125,148	131,462	110,649
Acquisition related costs		5,770	8,815
Other, net	229,842	240,192	173,437
Total operating expenses	3,368,385	3,613,818	2,563,319
OPERATING INCOME	165,987	41,105	201,826
OTHER INCOME (EXPENSE):
Interest income	7,928	8,236	14,376
Interest expense	(77,380)	(80,383)	(86,517)
Purchase accounting gain (adjustment)		(5,711)	15,586
Other, net	(10,639)	(13,417)	630
Total other expense, net	(80,091)	(91,275)	(55,925)
INCOME (LOSS) BEFORE INCOME TAXES	85,896	(50,170)	145,901
PROVISION (BENEFIT) FOR INCOME TAXES	34,739	(22,835)	49,551
NET INCOME (LOSS)	51,157	(27,335)	96,350
BASIC EARNINGS (LOSS) PER SHARE (in dollars per share)	$ 1.00	$ (0.52)	$ 1.73
DILUTED EARNINGS (LOSS) PER SHARE (in dollars per share)	$ 0.99	$ (0.52)	$ 1.70
Weighted average common shares:
Basic (in shares)	51,090	52,201	55,610
Diluted (in shares)	51,746	52,201	56,526
COMPREHENSIVE INCOME (LOSS):
Net income (loss)	51,157	(27,335)	96,350
Proportionate share of other companies foreign currency translation adjustment, net of taxes	(251)	(295)	637
Net unrealized appreciation (depreciation) on marketable securities, net of taxes	316	534	(745)
TOTAL COMPREHENSIVE INCOME (LOSS)	$ 51,222	$ (27,096)	$ 96,242