Nature of Operations and Summary of Significant Accounting Policies - Passenger and Ground Handling Revenues (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
ExpressJet United Express ERJ Agreement and ExpressJet American ERJ145 Agreement
Other Revenue Items
Deemed rental income under code-share agreement	$ 572.7	$ 516.0	$ 504.9

Represents the deemed rental income under the entity's code-share agreements, which is recorded as passenger revenue.

No definition available.

Name:	skyw_DeemedRentalIncomeUnderCodeShareAgreements
Namespace Prefix:	skyw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration