Cumulative Loss Position Period

No definition available.

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- Details

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- Definition

Net operating loss expiration amount

+ References

No definition available.

+ Details

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- Definition

Operating Loss Carryforwards, Expiration Period

+ References

No definition available.

+ Details

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- Definition

Unrecognized Tax Benefit Resulting In Net Operating Loss Carryforward

+ References

No definition available.

+ Details

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- Definition

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section S99

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-Subparagraph (SAB TOPIC 6.I)

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-Topic 740

-SubTopic 10

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32559-109319

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

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-SubTopic 10

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-Paragraph 15A

-Subparagraph (a)

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+ Details

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15A

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 45

-Paragraph 20

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes [Line Items]
Federal pre-tax NOL carry forwards	$ 9,600,000,000us-gaap_OperatingLossCarryforwards
State tax benefits	111,000,000
Federal statutory income tax rate	35.00%
Cumulative loss position at the end of 2014	3 years
Current valuation allowances	4,751,000,000	4,591,000,000
Increase (decrease) in current valuation allowances	160,000,000
Unrecognized tax benefits	9,000,000us-gaap_UnrecognizedTaxBenefits	14,000,000us-gaap_UnrecognizedTaxBenefits	19,000,000us-gaap_UnrecognizedTaxBenefits	24,000,000us-gaap_UnrecognizedTaxBenefits
Unrecognized tax benefits that would impact effective tax rate if recognized	7,000,000
United Airlines, Inc.
Income Taxes [Line Items]
Current valuation allowances	4,721,000,000	4,561,000,000
Increase (decrease) in current valuation allowances	160,000,000
2024
Income Taxes [Line Items]
Net operating loss expiration amount	1,100,000,000
2025
Income Taxes [Line Items]
Net operating loss expiration amount	2,500,000,000
2026
Income Taxes [Line Items]
Net operating loss expiration amount	2,000,000,000
Thereafter
Income Taxes [Line Items]
Net operating loss expiration amount	$ 4,000,000,000
Minimum
Income Taxes [Line Items]
State tax benefits of the NOL carry forwards expiration period, years	5 years
Maximum
Income Taxes [Line Items]
State tax benefits of the NOL carry forwards expiration period, years	20 years