Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011 subsidiary segment	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011 subsidiary segment	Dec. 31, 2010	Dec. 31, 2009
Segment Reporting
Operating segments number	2								2
Number of subsidiaries representing operating segments	2								2
Segment Reporting
Operating revenues	$ 899,850	$ 955,425	$ 933,697	$ 865,951	$ 796,285	$ 686,858	$ 649,759	$ 632,243	$ 3,654,923	$ 2,765,145	$ 2,613,614
Operating expense (income)									3,613,818	2,563,319	2,401,419
Depreciation and amortization expense									254,182	236,499	221,548
Interest expense.									80,383	86,517	86,330
Identifiable intangible assets, other than goodwill	19,497				21,747				19,497	21,747	23,997
Total assets.	4,281,908				4,456,148				4,281,908	4,456,148	4,310,802
Capital expenditures (including non - cash)									199,756	181,077	439,402
Operating segment
Segment Reporting
Segment profit (loss)									(39,278)	115,309	125,865
SkyWest
Segment Reporting
Operating revenues									2,002,830	1,904,472	1,731,346
Operating expense (income)									1,893,909	1,759,784	1,591,311
Depreciation and amortization expense									147,520	144,002	132,513
Interest expense.									50,907	53,622	45,729
Segment profit (loss)									58,014	91,066	94,306
Total assets.	2,595,901				2,587,371				2,595,901	2,587,371	2,436,700
Capital expenditures (including non - cash)									166,998	158,787	406,231
ExpressJet
Segment Reporting
Operating revenues									1,640,837	855,095	880,846
Operating expense (income)									1,714,481	804,110	815,699
Depreciation and amortization expense									106,662	92,497	89,035
Interest expense.									25,142	27,933	34,224
Segment profit (loss)									(98,786)	23,052	30,923
Identifiable intangible assets, other than goodwill	19,497				21,747				19,497	21,747	23,997
Total assets.	1,686,007				1,859,138				1,686,007	1,859,138	1,874,102
Capital expenditures (including non - cash)									32,758	22,290	33,171
Other
Segment Reporting
Operating revenues									11,256	5,578	1,422
Operating expense (income)									5,428	(575)	(5,591)
Interest expense.									4,334	4,962	6,377
Segment profit (loss)									$ 1,494	$ 1,191	$ 636