Passenger and Ground Handling Revenue (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($) aircraft	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) aircraft agreement	Sep. 30, 2015 USD ($)
Agreements with other airlines
Percentage of ASMs flown under fixed-fee arrangements			95.50%
Percentage of ASMs flown under pro-rate arrangements			4.50%
Revenue | $	$ 799,776	$ 794,004	$ 2,363,190	$ 2,342,819
Early lease return costs | $	$ 9,200		$ 19,400
Sky West Airlines Inc | Delta Connection Prorate Agreement
Agreements with other airlines
Notice period for termination of agreement			30 days
Sky West Airlines Inc | United Express Prorate Agreement
Agreements with other airlines
Notice period for termination of agreement			120 days
Sky West Airlines Inc | American Prorate Agreement
Agreements with other airlines
Notice period for termination of agreement			120 days
ExpressJet | United Express Agreements
Agreements with other airlines
Number of contingent agreement extension provisions | agreement			2
Agreement, contingent extension provision duration			1 year
ExpressJet | American Prorate Agreement
Agreements with other airlines
Notice period for termination of agreement			120 days
CRJ 200 | Sky West Airlines Inc | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			48
CRJ 200 | Sky West Airlines Inc | Delta Connection Prorate Agreement
Agreements with other airlines
Number of aircraft under contract			21
CRJ 200 | Sky West Airlines Inc | United Express Agreements
Agreements with other airlines
Number of aircraft under contract			54
CRJ 200 | Sky West Airlines Inc | United Express Prorate Agreement
Agreements with other airlines
Number of aircraft under contract			21
CRJ 200 | Sky West Airlines Inc | American Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			12
CRJ 200 | Sky West Airlines Inc | American Prorate Agreement
Agreements with other airlines
Number of aircraft under contract			5
CRJ 200 | ExpressJet | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			38
CRJ 200 | ExpressJet | American Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			11
CRJ 200 | ExpressJet | American Prorate Agreement
Agreements with other airlines
Number of aircraft under contract			3
CRJ 700
Agreements with other airlines
Number of aircraft removed from service	6		9
CRJ 700 | Sky West Airlines Inc | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			29
CRJ 700 | Sky West Airlines Inc | United Express Agreements
Agreements with other airlines
Number of aircraft under contract			47
CRJ 700 | Sky West Airlines Inc | Alaska Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			5
CRJ 700 | Sky West Airlines Inc | American Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			13
CRJ 700 | ExpressJet | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			36
CRJ 900 | Sky West Airlines Inc | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			36
CRJ 900 | ExpressJet | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			28
E 175 | Delta Connection Agreements
Agreements with other airlines
Number of additional aircrafts into service			14
E 175 | United Express Agreements
Agreements with other airlines
Number of additional aircrafts into service			16
E 175 | Alaska Capacity Purchase Agreement
Agreements with other airlines
Number of additional aircrafts into service			7
E 175 | Sky West Airlines Inc | Delta Connection Agreements
Agreements with other airlines
Number of aircraft under contract			5
E 175 | Sky West Airlines Inc | United Express Agreements
Agreements with other airlines
Number of aircraft under contract			49
E 175 | Sky West Airlines Inc | Alaska Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			13
ERJ 145 | ExpressJet | United Express Agreements
Agreements with other airlines
Number of aircraft under contract			149
ERJ 145 | ExpressJet | American Capacity Purchase Agreement
Agreements with other airlines
Number of aircraft under contract			14
ERJ 135 | ExpressJet | United Express Agreements
Agreements with other airlines
Number of aircraft under contract			5