Schedule of Acquisition of Aircrafts and Related Spare Engines (Detail) (USD $) In Billions, unless otherwise specified	Mar. 31, 2013
Commitments and Contingencies Disclosure [Line Items]
2013	$ 1.6
2014	1.9
2015	1.9
2016	3.0
2017	2.5
After 2017	6.8
Total commitments	$ 17.7

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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