v3.3.0.814

Derivative Instruments - Location and Amounts of Derivative Gains and Losses in Condensed Consolidated Statements of Income (Detail) - Derivatives Not Designated as Hedging Instruments [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Commodity contracts [Member] | Net realized and unrealized gains (losses) on fuel price derivatives [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ 7,922	$ 14,773	$ 4,671	$ 9,057
Foreign Currency Exchange Contract [Member] | Net unrealized gain (loss) on currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	0	8,177	21,967	6,893
Currency Swap [Member] | Net unrealized gain (loss) on currency forward contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain or (Loss) Recognized in Income on Derivative	$ (100)	$ 0	$ (100)	$ 0

X

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 815



-SubTopic 10



-Section 50



-Paragraph 4A



-Subparagraph (b)



-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5618551-113959



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



-Publisher FASB



-Name Accounting Standards Codification



-Topic 815



-SubTopic 10



-Section 50



-Paragraph 4C



-Subparagraph (a),(c),(d),(e)



-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624171-113959

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- Definition

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+ References

No definition available.

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