Airline, Capacity Purchase Arrangements, Carriers

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- Definition

Airline, Capacity Purchase Arrangements, Percent

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Number of Aircraft under Capacity Purchase Agreement

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Operating Leases, Number of Units

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Operating Leases, Number of Additional Units That Could Be Leased

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Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional

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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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- Definition

Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

-SubTopic 10

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6394976&loc=d3e25336-109308

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts).

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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No definition available.

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- Definition

The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

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COMMITMENTS (Details) $ in Millions	3 Months Ended		9 Months Ended
COMMITMENTS (Details) $ in Millions	Sep. 30, 2015 USD ($) aircraft carriers	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($) aircraft carriers	Sep. 30, 2014 USD ($)
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Capacity purchase arrangements (carriers) \| carriers	3		3
Capacity purchase arrangements (percent)	100.00%		100.00%
Rent expense	$ 77	$ 74	$ 217	$ 215
B-737 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Committed to Purchase (in Aircraft) \| aircraft	71		71
Options to Purchase Additional (in Aircraft) \| aircraft	46		46
B737-900ER [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Committed to Purchase (in Aircraft) \| aircraft	34		34
B-737-Max [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Committed to Purchase (in Aircraft) \| aircraft	37		37
Q400 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Committed to Purchase (in Aircraft) \| aircraft	2		2
Options to Purchase Additional (in Aircraft) \| aircraft	5		5
Subleased and Operated by Other Carrier [Member] \| Non Operating Aircraft [Member] \| CRJ-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	8		8
Aircraft [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Remainder of 2015	$ 13		$ 13
2016	112		112
2017	103		103
2018	98		98
2019	90		90
Thereafter	548		548
Total	$ 964		$ 964
Aircraft [Member] \| Operated by Skywest [Member] \| B-737 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	27		27
Aircraft [Member] \| Operated by Skywest [Member] \| Q400 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	15		15
Aircraft [Member] \| Operated by Skywest [Member] \| CRJ-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	6		6
Aircraft [Member] \| Operated by Skywest [Member] \| E175 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	15		15
Aircraft [Member] \| Operated by Skywest [Member] \| E-175 [Domain]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of additional aircraft that could be leased (in aircraft) \| aircraft	8		8
Aircraft [Member] \| Operated by Skywest [Member] \| Additional E175 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	8		8
Building [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Remainder of 2015	$ 25		$ 25
2016	98		98
2017	93		93
2018	43		43
2019	41		41
Thereafter	209		209
Total	509		509
Aircraft Commitments [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Remainder of 2015	51		51
2016	601		601
2017	544		544
2018	428		428
2019	372		372
Thereafter	650		650
Total	2,646		2,646
Capacity Purchase Agreements [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Remainder of 2015	16		16
2016	67		67
2017	58		58
2018	60		60
2019	64		64
Thereafter	623		623
Total	$ 888		$ 888
Capacity Purchase Agreements [Member] \| Aircraft [Member] \| CRJ-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under capacity purchase agreement \| aircraft	2		2
Capacity Purchase Agreements [Member] \| Aircraft [Member] \| Operating Aircraft [Member] \| CRJ-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under capacity purchase agreement \| aircraft	8		8
Capacity Purchase Agreements [Member] \| Aircraft [Member] \| Operating Aircraft [Member] \| E175 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under capacity purchase agreement \| aircraft	8		8
Capacity Purchase Agreements [Member] \| Aircraft [Member] \| Operating Aircraft [Member] \| Delivered E175 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under operating lease (in Aircraft) \| aircraft	3		3
Capacity Purchase Agreements [Member] \| Aircraft [Member] \| Operated by Skywest [Member] \| Operating Aircraft [Member] \| CRJ-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Number of aircraft under capacity purchase agreement \| aircraft	6		6