Business Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 item	Sep. 30, 2013
Business Segments
Number of reportable operating business segments			3
Revenue:
Total revenue	$ 11,713,463	$ 10,493,661	$ 33,606,834	$ 31,157,294
Gross profit:
Gross profit	214,608	186,341	594,156	557,178
Income from operations:
Income from operations	74,103	64,203	198,219	199,880
Aviation Segment
Revenue:
Total revenue	4,675,530	4,179,018	13,361,838	11,854,676
Gross profit:
Gross profit	96,235	89,758	246,980	242,783
Marine segment
Revenue:
Total revenue	3,725,612	3,575,777	10,738,646	11,260,025
Gross profit:
Gross profit	49,404	40,223	146,087	134,237
Land Segment
Revenue:
Total revenue	3,312,321	2,738,866	9,506,350	8,042,593
Gross profit:
Gross profit	68,969	56,360	201,089	180,158
Operating Segments
Income from operations:
Income from operations	87,371	73,127	237,476	229,703
Operating Segments \| Aviation Segment
Income from operations:
Income from operations	47,330	41,002	114,553	109,755
Operating Segments \| Marine segment
Income from operations:
Income from operations	20,933	17,019	62,903	56,340
Operating Segments \| Land Segment
Income from operations:
Income from operations	19,108	15,106	60,020	63,608
Corporate
Income from operations:
Income from operations	$ 13,268	$ 8,924	$ 39,257	$ 29,823

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.

+ Details

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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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