Equity awards conversion rate.

No definition available.

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- Definition

Equity awards payment percentage

+ References

No definition available.

+ Details

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Namespace Prefix:	ual_
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Balance Type:	na
Period Type:	duration

- Definition

Fixed Cash Equivalent Price Of Predecessor Awards

+ References

No definition available.

+ Details

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- Definition

Number of days used to compute performance period average closing price of restricted stock units

+ References

No definition available.

+ Details

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Namespace Prefix:	ual_
Data Type:	xbrli:decimalItemType
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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Contractual Life

+ References

No definition available.

+ Details

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Vesting Date

+ References

No definition available.

+ Details

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Namespace Prefix:	ual_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (k)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph j

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-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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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(2)

-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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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (f)(2)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph e(2)(c)

-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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Share-Based Compensation Plans - Additional Information (Detail) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	1 Months Ended		3 Months Ended	12 Months Ended		1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended			1 Months Ended	12 Months Ended							3 Months Ended
	Sep. 30, 2010	May 31, 2010	Dec. 31, 2010	Dec. 31, 2012 D	Dec. 31, 2010	Feb. 29, 2012 Restricted Stock	Dec. 31, 2012 Restricted Stock	Dec. 31, 2011 Restricted Stock	Dec. 31, 2010 Restricted Stock	Feb. 29, 2012 Restricted Stock Units	Dec. 31, 2012 Restricted Stock Units	Dec. 31, 2011 Restricted Stock Units	Dec. 31, 2010 Restricted Stock Units	Feb. 29, 2012 Performance Shares	Dec. 31, 2012 Stock Options	Dec. 31, 2012 Stock Options Minimum	Dec. 31, 2012 Stock Options Maximum	Dec. 31, 2012 Restricted Stock and Restricted Stock Units	Dec. 31, 2011 Restricted Stock and Restricted Stock Units	Dec. 31, 2010 Restricted Stock and Restricted Stock Units	Dec. 31, 2012 Continental Airlines Inc Predecessor	Dec. 31, 2010 United Airlines, Inc.
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of days used to compute performance period average closing price of restricted stock units				20
Share-Based Compensation, award granted						500	545	536	212	600	1,986	3,655	1,395	1,300
Share-Based Compensation, vesting period						3 years				3 years				3 years		3 years	4 years				3 years
Share-Based Compensation, vesting date														Dec. 31, 2014
Equity awards conversion rate																					1.05
Equity awards fair value																		$ 27	$ 7	$ 33	$ 78
Equity awards payment percentage																					150.00%
Closing price of common stock	$ 23.66	$ 22.33																			$ 23.48
Cash settlements for restricted stock unit			19								35	57	84									18
Stock options, contractual term, years															10 years
Dividend yield					0.00%
Liability due to PBRSUs converted to fixed cash equivalent											$ 57