Document and Entity Information Document - shares	3 Months Ended
	Mar. 31, 2018	May 01, 2018
Document Information [Line Items]
Entity Registrant Name	GENESEE & WYOMING INC.
Entity Central Index Key	0001012620
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Document Type	10-Q
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Class A Common Shares [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		60,149,625
Class B Common Shares [Member]
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		671,138