Condensed Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Net cash provided by (used in) operating activities	$ 79,674	$ (5,944)
Investing activities:
Proceeds from sale of property and equipment		43
Pre-delivery deposits for flight equipment, net of refunds	1,444	(12,724)
Purchase of property and equipment, net	(9,823)	(1,488)
Net cash used in investing activities	(8,379)	(14,169)
Financing activities:
Proceeds from issuance of common stock	213
Proceeds from sale leaseback transactions	5,627
Excess tax benefits from share-based compensation	825
Repurchase of restricted common stock	(457)
Net cash provided by financing activities	6,208
Net increase (decrease) in cash and cash equivalents	77,503	(20,113)
Cash and cash equivalents at beginning of period	343,328	82,714
Cash and cash equivalents at end of period	420,831	62,601
Cash payments for:
Interest paid	12	1,149
Taxes paid	$ 1,486	$ 123