Segment Reporting (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) segment
Segment Reporting
Number of operating segments | segment			3
Number of reporting segments | segment	2
Operating revenues	$ 2,713,491	$ 2,127,106	$ 2,971,963
Operating expense	2,437,624	2,018,304	2,459,705
Depreciation and amortization expense	440,198	474,959	368,098
Special items	84,592		21,869
Interest expense	123,122	123,173	127,755
Segment profit (loss)	152,745	(14,371)	384,503
Total assets	7,125,947	6,887,622	6,657,129
Capital expenditures (including non-cash)	567,037	460,483	846,470
SkyWest Airlines [Member]
Segment Reporting
Operating revenues	2,192,432	1,636,762	2,478,681
Operating expense	2,177,524	1,716,808	2,214,632
Depreciation and amortization expense	210,281	221,216	168,246
Special items	84,592		18,508
Interest expense	13,360	12,381	13,525
Segment profit (loss)	1,548	(92,427)	250,524
Total assets	2,957,745	2,804,259	2,728,964
Capital expenditures (including non-cash)	128,712	124,825	270,191
Express Jet Airlines Inc [Member]
Segment Reporting
Operating revenues			24,050
Operating expense			28,690
Depreciation and amortization expense			971
Special items			3,361
Segment profit (loss)			(4,640)
SkyWest Leasing
Segment Reporting
Operating revenues	521,059	490,344	469,232
Operating expense	260,100	301,496	216,383
Depreciation and amortization expense	229,917	253,743	198,881
Interest expense	109,762	110,792	114,230
Segment profit (loss)	151,197	78,056	138,619
Total assets	4,168,202	4,083,363	3,928,165
Capital expenditures (including non-cash)	$ 438,325	$ 335,658	$ 576,279