Segment Reporting (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) segment	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Segment Reporting
Number of operating segments \| segment			3
Operating revenues	$ 760,295	$ 829,275	$ 2,228,372	$ 2,418,190
Operating expense	613,854	691,350	1,841,419	2,065,412
Depreciation and amortization expense	92,795	86,088	272,929	246,386
Special items			21,869
Interest expense	31,606	31,440	96,884	86,485
Segment profit (loss)	118,738	109,925	348,517	275,455
Identifiable intangible assets, other than goodwill		1,224		1,224
Total assets	6,597,659	6,184,860	6,597,659	6,184,860	$ 6,313,212
Capital expenditures (including non-cash)	101,991	321,566	652,232	954,071
Segments
Segment Reporting
Segment profit (loss)	114,835	106,485	290,069	266,293
SkyWest Airlines
Segment Reporting
Operating revenues	641,947	607,052	1,854,803	1,750,827
Operating expense	560,646	512,278	1,651,966	1,505,298
Depreciation and amortization expense	43,353	39,651	124,048	115,979
Special items			18,508
Interest expense	3,165	4,044	10,699	12,722
Total assets	2,744,191	2,251,563	2,744,191	2,251,563
Capital expenditures (including non-cash)	67,394	44,689	184,019	121,010
SkyWest Airlines \| Segments
Segment Reporting
Segment profit (loss)	78,136	90,730	192,138	232,807
ExpressJet Airlines Inc
Segment Reporting
Operating revenues		140,155	24,050	444,943
Operating expense		139,736	28,690	455,084
Depreciation and amortization expense		8,683	971	30,044
Special items			3,361
Interest expense		649		2,264
Identifiable intangible assets, other than goodwill		1,224		1,224
Total assets		565,266		565,266
Capital expenditures (including non-cash)		3,069		5,996
ExpressJet Airlines Inc \| Segments
Segment Reporting
Segment profit (loss)		(230)	(4,640)	(12,405)
SkyWest Leasing
Segment Reporting
Operating revenues	118,348	82,068	349,519	222,420
Operating expense	53,208	39,336	160,763	105,030
Depreciation and amortization expense	49,442	37,754	147,910	100,363
Interest expense	28,441	26,747	86,185	71,499
Total assets	3,853,468	3,368,031	3,853,468	3,368,031
Capital expenditures (including non-cash)	34,597	273,808	468,213	827,065
SkyWest Leasing \| Segments
Segment Reporting
Segment profit (loss)	$ 36,699	$ 15,985	$ 102,571	$ 45,891

Represents the special charges and write down value of assets related to aircrafts and facilities.

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