Consolidated Statements of Changes in Equity Statement - USD ($) $ in Thousands	Total	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss)/ Income [Member]	Treasury Stock [Member]	Noncontrolling Interest [Member]	Class A Common Stock [Member] Common Stock [Member]	Class B Common Stock [Member] Common Stock [Member]	Conversion of Class B Common Stock to Class A Common Stock [Member]	Conversion of Class B Common Stock to Class A Common Stock [Member] Class A Common Stock [Member] Common Stock [Member]	Conversion of Class B Common Stock to Class A Common Stock [Member] Class B Common Stock [Member] Common Stock [Member]	Accounting Standards Update 2018-02 [Member] Retained Earnings [Member]	Accounting Standards Update 2018-02 [Member] Accumulated Other Comprehensive (Loss)/ Income [Member]
Stockholders' equity, balance at Dec. 31, 2015	$ 2,519,461	$ 1,355,345	$ 1,544,676	$ (153,457)	$ (227,808)	$ 0	$ 697	$ 8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to Genesee & Wyoming Inc.	141,137		141,137
Net income/(loss) attributable to noncontrolling interest	(41)					(41)
Net income including portion attributable to noncontrolling interest	141,096
Other comprehensive income/(loss) attributable to G&W				(92,517)
Other comprehensive income/(loss) attributable to noncontrolling interest						8,549
Other comprehensive income/(loss) including portion attributable to noncontrolling interest	(83,968)
Value of stock issued - equity offering	285,756	285,716					40
Conversion of Class B shares to Class A common stock									$ 0	$ 0	$ 0
Value of stock issued for stock-based compensation	10,363	10,358					5
Compensation cost related to stock-based compensation	18,884	18,884
Income tax deficiencies from stock-based compensation	(281)	(281)
Value of treasury stock repurchased	(4,540)				(4,540)
Issuance of noncontrolling interest	300,342	39,585		48,658		212,099
Other	8	8
Stockholders' equity, balance at Dec. 31, 2016	3,187,121	1,709,615	1,685,813	(197,316)	(232,348)	220,607	742	8
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to Genesee & Wyoming Inc.	549,051		549,051
Net income/(loss) attributable to noncontrolling interest	7,727					7,727
Net income including portion attributable to noncontrolling interest	556,778
Other comprehensive income/(loss) attributable to G&W	91,782			91,782
Other comprehensive income/(loss) attributable to noncontrolling interest						17,296
Other comprehensive income/(loss) including portion attributable to noncontrolling interest	109,078
Conversion of Class B shares to Class A common stock									0	(1)	(1)
Value of stock issued for stock-based compensation	12,322	12,319					3
Compensation cost related to stock-based compensation	17,476	17,476
Value of treasury stock repurchased	(4,603)				(4,603)
Value of stock issued from sale of unregistered securities	17,491	17,489					2
Other	429	433				(4)
Stockholders' equity, balance at Dec. 31, 2017	3,896,092	1,757,332	2,234,864	(105,534)	(236,951)	245,626	748	7
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income attributable to Genesee & Wyoming Inc.	244,418		244,418
Net income/(loss) attributable to noncontrolling interest	9,908					9,908
Net income including portion attributable to noncontrolling interest	254,326
Other comprehensive income/(loss) attributable to G&W	(37,952)			(37,952)
Other comprehensive income/(loss) attributable to noncontrolling interest						(23,633)
Other comprehensive income/(loss) including portion attributable to noncontrolling interest	(61,585)
Conversion of Class B shares to Class A common stock									$ 0	$ (2)	$ (2)
Value of stock issued for stock-based compensation	10,023	10,021					2
Compensation cost related to stock-based compensation	17,652	17,652
Value of treasury stock repurchased	(462,901)				(462,901)
Distributions to Noncontrolling Interest	(23,583)					(23,583)
United States Tax Cuts and Jobs Act 2017, Reclassification from AOCI to Retained Earnings	0			(2,970)
United States Tax Cuts and Jobs Act 2017, Reclassification from AOCI to Retained Earnings | Adjustments for New Accounting Principle, Early Adoption [Member]												$ 2,970	$ (2,970)
Other	28					28
Stockholders' equity, balance at Dec. 31, 2018	$ 3,630,052	$ 1,785,005	$ 2,482,252	$ (146,456)	$ (699,852)	$ 208,346	$ 752	$ 5