Segment Reporting (Details) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting
Operating segments number | segment				2
Number of operating subsidiaries representing operating segments | segment				2
Segment Reporting
Operating revenues		$ 788,417	$ 816,574	$ 1,548,815	$ 1,588,960
Operating expense		718,485	803,330	1,444,807	1,603,490
Depreciation and amortization expense		64,659	64,252	130,350	126,567
Interest expense		18,081	16,138	36,546	31,814
Segment profit (loss)		52,548	(5,001)	68,798	(48,175)
Identifiable intangible assets, other than goodwill, net		11,623	13,873	11,623	13,873	$ 12,748
Total assets		4,838,554	4,279,841	4,838,554	4,279,841	$ 4,409,928
Capital expenditures (including non - cash)		253,800	242,360	523,070	297,508
Corporate/Consolidating
Segment Reporting
Operating revenues		5,204	74	8,975	948
Operating expense		651	(112)	1,703	(20)
Depreciation and amortization expense		262		524
Interest expense			734		1,509
SkyWest Airlines
Segment Reporting
Operating revenues		478,121	475,501	926,191	922,543
Operating expense		412,244	433,551	818,263	859,193
Depreciation and amortization expense		42,716	41,958	86,484	81,958
Interest expense		15,440	10,661	29,466	20,687
Total assets		3,406,620	2,688,143	3,406,620	2,688,143
Capital expenditures (including non - cash)		246,322	234,986	508,347	282,842
Express Jet Airlines Inc
Segment Reporting
Operating revenues		305,092	340,599	613,649	665,469
Operating expense		305,590	369,891	624,841	744,317
Depreciation and amortization expense		21,681	22,294	43,342	44,609
Interest expense		2,641	4,743	7,080	9,618
Identifiable intangible assets, other than goodwill, net		11,623	13,873	11,623	13,873
Total assets		1,431,934	1,591,698	1,431,934	1,591,698
Capital expenditures (including non - cash)		7,478	7,374	14,723	14,666
Segment [Member]
Segment Reporting
Segment profit (loss)	[1]	51,851	(2,894)	67,462	(46,344)
Segment [Member] | Corporate/Consolidating
Segment Reporting
Segment profit (loss)	[1]	4,553	(148)	7,272	(541)
Segment [Member] | SkyWest Airlines
Segment Reporting
Segment profit (loss)	[1]	50,437	31,289	78,462	42,663
Segment [Member] | Express Jet Airlines Inc
Segment Reporting
Segment profit (loss)	[1]	$ (3,139)	$ (34,035)	$ (18,272)	$ (88,466)

[1] Segment profit (loss) is equal to operating income less interest expense