Changes in Operations GRail Pro Forma (Details) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2016 USD ($) $ / shares $ / AUD	May 03, 2017 $ / AUD	Dec. 01, 2016 $ / AUD
Operating revenues	$ 1,526,122
Net income attributable to Genesee & Wyoming Inc.	$ 122,779
Basic earnings per common share \| $ / shares	$ 2.15
Diluted earnings per common share \| $ / shares	$ 2.11
Foreign currency exchange rate \| $ / AUD	0.74	1.29	0.74
MIRA [Member]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			48.90%
Acquisition-related Costs [Member] \| Pro Forma [Member] \| GRail [Member]
Business Acquisition, Pro Forma Income (loss) from Continuing Operations, Before Tax	$ 4,600
Business Acquisition, Pro Forma Income (Loss) from Continuing Operations, Net of Tax	$ 4,400

Business Acquisition, Pro Forma Income (loss) from Continuing Operations, Before Tax

No definition available.

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- Definition

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.

+ References

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=79982066&loc=d3e1392-128463

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- Definition

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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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

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- Definition

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.

+ References

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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.

+ References

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- Definition

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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- Definition

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

+ References

No definition available.

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