Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
OPERATING ACTIVITIES:
Net income	$ 31,831	$ 21,703
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	16,892	11,970
Loss on aircraft and other equipment disposals	1,315	56
Provision for obsolescence of expendable parts, supplies and fuel	180	90
Amortization of deferred financing costs and original issue discount	183	137
Stock-based compensation expense	2,309	986
Deferred income taxes	4,207	(854)
Excess tax benefits from stock-based compensation	(607)	(116)
Changes in certain assets and liabilities:
Restricted cash	(1,827)	(1,323)
Accounts receivable	4,019	(936)
Expendable parts, supplies and fuel	2,748	(984)
Prepaid expenses	(2,287)	(14,506)
Other current assets	420	567
Accounts payable	5,123	7,280
Accrued liabilities	5,331	12,353
Air traffic liability	37,987	46,469
Net cash provided by operating activities	107,824	82,892
INVESTING ACTIVITIES:
Purchase of investment securities	(147,591)	(143,558)
Proceeds from maturities of investment securities	95,627	82,696
Purchase of property and equipment, including pre-delivery deposits	(13,097)	(31,628)
Interest during refurbishment of aircraft	(123)	(196)
Proceeds from sale of property and equipment	243	112
Investment in unconsolidated affiliates, net	(709)	(960)
Change in deposits and other assets	10,187	712
Net cash used in investing activities	(55,463)	(92,822)
FINANCING ACTIVITIES:
Excess tax benefits from stock-based compensation	607	116
Proceeds from exercise of stock options	189	1,022
Repurchase of common stock	(23,180)	(441)
Principal payments on long-term debt	(2,877)	(1,959)
Payments for sale of ownership interest in subsidiary	(50)
Net cash used in financing activities	(25,311)	(1,262)
Net change in cash and cash equivalents	27,050	(11,192)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	89,557	150,740
CASH AND CASH EQUIVALENTS AT END OF PERIOD	116,607	139,548
Non- cash transactions:
Assets acquired in sale of ownership interest in subsidiary	$ 56