Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 item	Sep. 30, 2012
Business Segments
Number of reportable operating business segments			3
Revenue:
Total revenue	$ 10,493,661	$ 9,911,673	$ 31,157,294	$ 29,009,525
Gross profit:
Gross profit	186,341	180,752	557,178	510,110
Income from operations:
Income from operations	64,203	71,048	199,880	202,662
Operating Segments
Income from operations:
Income from operations	73,127	85,289	229,703	238,010
Operating Segments \| Aviation segment
Revenue:
Total revenue	4,179,018	3,823,338	11,854,676	10,782,756
Gross profit:
Gross profit	89,758	84,197	242,783	218,282
Income from operations:
Income from operations	41,002	39,808	109,755	92,601
Operating Segments \| Marine segment
Revenue:
Total revenue	3,575,777	3,630,094	11,260,025	11,301,429
Gross profit:
Gross profit	40,223	53,960	134,237	160,785
Income from operations:
Income from operations	17,019	27,296	56,340	82,672
Operating Segments \| Land segment
Revenue:
Total revenue	2,738,866	2,458,241	8,042,593	6,925,340
Gross profit:
Gross profit	56,360	42,595	180,158	131,043
Income from operations:
Income from operations	15,106	18,185	63,608	62,737
Corporate
Income from operations:
Income from operations	$ 8,924	$ 14,241	$ 29,823	$ 35,348

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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