Changes in Operations Pro Forma Financial Results (Details) Share data in Millions, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended			1 Months Ended	12 Months Ended							12 Months Ended	3 Months Ended	12 Months Ended
	Dec. 31, 2012 USD ($)	Sep. 30, 2012 USD ($)	Jun. 30, 2012 USD ($)	Mar. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Sep. 30, 2011 USD ($)	Jun. 30, 2011 USD ($)	Mar. 31, 2011 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2011 USD ($)	Dec. 31, 2010 USD ($)	Dec. 31, 2010 FreightLink [Member] USD ($)	Dec. 31, 2011 FreightLink [Member] USD ($)	Dec. 31, 2011 FreightLink [Member] AUD	Dec. 31, 2010 FreightLink [Member] USD ($)	Dec. 01, 2010 FreightLink [Member]	Sep. 30, 2010 FreightLink [Member] USD ($)	Jun. 30, 2010 FreightLink [Member] USD ($)	Mar. 31, 2010 FreightLink [Member] USD ($)	Dec. 31, 2012 RailAmerica [Member] USD ($)	Dec. 28, 2012 RailAmerica [Member] USD ($)	Dec. 31, 2012 RailAmerica [Member] USD ($)	Dec. 31, 2012 AUSTRALIA
Business Acquisition [Line Items]
Pro Forma acquisition related costs, net of tax																				$ 14,500,000		$ 12,900,000
Pro Forma, business combination, financing related costs, net of tax																						9,000,000
Pro Forma costs incurred with redemption of senior secured notes																						55,000,000
Pro Forma if converted shares excluded from diluted shares									6.0
Statutory income tax rate									35.00%	35.00%	35.00%												30.00%
Revenues	227,316,000	222,745,000	217,419,000	207,436,000	210,386,000	217,210,000	209,589,000	191,911,000	874,916,000	829,096,000	630,195,000		11,600,000								151,065,000
Income from operations	33,660,000	52,875,000	62,473,000	41,314,000	45,388,000	56,023,000	51,165,000	39,203,000	190,322,000	191,779,000	130,410,000		10,300,000								26,137,000
Stamp duty									0	0	12,625,000		11,500,000	11,800,000
Acquisition costs									18,592,000	0	0	28,200,000			7,800,000					18,600,000
Foreign currency exchange rate, translation													0.99			0.96	0.91	0.88	0.90
Pro Forma Information [Abstract]
Operating revenues									1,472,438,000	1,376,070,000	717,306,000
Net income attributable to Genesee & Wyoming Inc.									57,478,000	127,408,000	107,420,000
Series A-1 Preferred Stock dividend									17,500,000	17,500,000	0
Net income available to common stockholders									$ 39,978,000	$ 109,908,000	$ 107,420,000
Basic earnings per common share from continuing operations									$ 0.94	$ 2.35	$ 2.70
Diluted earnings per common share from continuing operations									$ 0.88	$ 2.22	$ 2.50