Airline, Capacity Purchase Arrangements, Carriers

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- Definition

Airline, Capacity Purchase Arrangements, Percent

+ References

No definition available.

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- Definition

Sale Leaseback Leases, Number of Units (in Aircraft)

+ References

No definition available.

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- Definition

Unrecorded Unconditional Purchase Obligation, Additional Minimum Quantity Required

+ References

No definition available.

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- Definition

Unrecorded Unconditional Purchase Obligation, Option to Purchase Additional

+ References

No definition available.

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- Definition

Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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 Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph b(i)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: 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 4: 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 maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Period Type:	instant

- Definition

Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The number of units (items of property) under operating lease arrangements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

The portion of the gain that will be recorded as income or a reduction in rent expense in future periods less amounts recognized in the current period.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 33

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 40

-Section 35

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=21918046&loc=d3e50609-112754

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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.

+ 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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 47

-Paragraph 7

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the four fiscal year following the latest fiscal year.

+ References

+ Details

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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.

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

+ References

+ Details

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- Definition

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).

+ References

+ Details

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- Definition

Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

No definition available.

+ Details

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COMMITMENTS (DETAILS) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 carriers	Dec. 31, 2011	Dec. 31, 2010
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Rent expense	$ 275	$ 275	$ 295
Capacity purchase arrangements, Carriers	3
Horizon [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Capacity purchase arrangements, Percent	100.00%
Aircraft Commitments [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
2013	372
2014	332
2015	254
2016	204
2017	322
Thereafter	1,488
Total	2,972
Capacity Purchase Agreements[Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
2013	17
2014	18
2015	18
2016	18
2017	19
Thereafter	8
Total	98
Engine Maintenance [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
2013	32
2014	26
2015	9
2016	0
2017	0
Thereafter	0
Total	67
Aircraft Leases [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013	142
2014	126
2015	104
2016	82
2017	51
Thereafter	80
Total	585
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Operating leases, number of leased assets (in aircraft)	63
Facility Leases [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2013	47
2014	42
2015	31
2016	22
2017	18
Thereafter	129
Total	289
Assets Leased to Others [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Operating leases, number of leased assets (in aircraft)	14
B737 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Additional commitment to purchase (in aircraft)	50
Commited to purchase (in aircraft)	71
Option to purchase additional (in aircraft)	69
B-737-700 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Sale leaseback transaction, deferred gain	$ 3
B-737-700 [Member] \| Aircraft Leases [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Sale leaseback transaction, number of units (in aircraft)	3
B737-900ER [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Commited to purchase (in aircraft)	34
B737 MAX [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Commited to purchase (in aircraft)	37
Q400 [Member]
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity [Abstract]
Option to purchase additional (in aircraft)	10