Changes in Operations GRail Pro Forma (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($) $ / shares $ / AUD	Dec. 01, 2016 $ / AUD
Operating revenues \| $	$ 493,837
Net income attributable to Genesee & Wyoming Inc. \| $	$ 27,268
Basic earnings per common share \| $ / shares	$ 0.48
Diluted earnings per common share \| $ / shares	$ 0.47
Foreign currency exchange rate \| $ / AUD	0.72	0.74
MIRA [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners		48.90%

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section S99
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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