Represents the maximum percentage of the participant's compensation eligible for the employer matching contribution.

No definition available.

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Namespace Prefix:	skyw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the maximum percentage of participant total compensation eligible for employer matching contribution after requisite service period.

+ References

No definition available.

+ Details

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Namespace Prefix:	skyw_
Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Represents the minimum service period required for Maximum employer matching contribution.

+ References

No definition available.

+ Details

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Namespace Prefix:	skyw_
Data Type:	xbrli:durationItemType
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Period Type:	duration

- Definition

Represents the maximum percentage of the employer's matching contribution for participant contributions based upon the length of service.

+ References

No definition available.

+ Details

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Namespace Prefix:	skyw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the first threshold percentage of the participant's compensation eligible for the employer's matching contribution based upon the length of service.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the third threshold percentage of the participant's compensation eligible for the employer's matching contribution based upon the length of service.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the second threshold percentage of the participant's compensation eligible for the employer's matching contribution based upon the length of service.

+ References

No definition available.

+ Details

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Namespace Prefix:	skyw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the age required to be completed by the employee to be eligible to participate in the plan.

+ References

No definition available.

+ Details

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Namespace Prefix:	skyw_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the estimated period of time over which an employee is required to provide service to participate in the defined benefit plan.

+ References

No definition available.

+ Details

Name:	skyw_DefinedBenefitPlanRequisiteServicePeriod
Namespace Prefix:	skyw_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of vesting for plan participants in their elective deferrals and rollover amounts.

+ References

No definition available.

+ Details

Name:	skyw_DefinedBenefitPlanVestingPercentageForElectiveDeferralsAndRolloverAmounts
Namespace Prefix:	skyw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the percentage of vesting of company matching contribution for plan participants based on the length of service.

+ References

No definition available.

+ Details

Name:	skyw_DefinedBenefitPlanVestingPercentageForEmployerMatchingContributionsBasedOnLengthOfService
Namespace Prefix:	skyw_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Retirement Plans and Employee Stock Purchase Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
SkyWest Plan
Retirement Plans
Service period required to be completed to be eligible to participate in plan	90 days
Required age for an employee to be eligible to participate in plan	18 years
Percentage of employer matching contribution based on length of service	100.00%
Company's combined contributions	$ 20.4	$ 19.3	$ 18.3
SkyWest Plan \| Pilot employees
Retirement Plans
Percentage of participant's compensation eligible for employer's matching contribution based upon length of service, threshold one	2.00%
Percentage of participant's compensation eligible for employer's matching contribution based upon length of service, threshold two	4.00%
Percentage of participant compensation eligible for employer's matching contribution based upon length of service, threshold three	6.00%
SkyWest Plan \| Non-pilot employees
Retirement Plans
Percentage of participant's compensation eligible for employer's matching contribution based upon length of service, threshold one	3.00%
Percentage of participant's compensation eligible for employer's matching contribution based upon length of service, threshold two	5.00%
Percentage of participant compensation eligible for employer's matching contribution based upon length of service, threshold three	7.00%
Atlantic Southeast and the ExpressJet Plans
Retirement Plans
Service period required to be completed to be eligible to participate in plan	90 days
Required age for an employee to be eligible to participate in plan	18 years
Company's combined contributions	$ 24.0	$ 27.2	$ 26.7
Atlantic Southeast Plan
Retirement Plans
Maximum percentage of participant's total compensation eligible for employer matching contribution	6.00%
Minimum service period required to be completed for eight percent matching contribution by the employer	10 years
Maximum percentage of participant's total compensation eligible for employer matching contribution after requisite service period	8.00%
Percentage of vesting for plan participants' elective deferrals and rollover amounts	100.00%
Atlantic Southeast Plan \| Minimum
Retirement Plans
Percentage of employer matching contribution based on length of service	20.00%
Percentage of vesting of company matching contribution based on length of service	10.00%
Atlantic Southeast Plan \| Maximum
Retirement Plans
Percentage of employer matching contribution based on length of service	75.00%
Percentage of vesting of company matching contribution based on length of service	100.00%