Schedule of Acquisition of Aircrafts and Related Spare Engines (Detail) (USD $) In Billions, unless otherwise specified	Sep. 30, 2012
United Continental Holdings Inc
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2012	$ 0.9
2013	1.5
2014	1.7
2015	1.9
2016	2.8
After 2016	9.6
Total commitments	18.4
United Air Lines Inc
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2012	0.3
2013	0.5
2014	0.8
2015	0.8
2016	2.0
After 2016	7.2
Total commitments	11.6
Continental Airlines Inc
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2012	0.6
2013	1.0
2014	0.9
2015	1.1
2016	0.8
After 2016	2.4
Total commitments	$ 6.8

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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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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