Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
CURRENT ASSETS: [Abstract]
Cash and cash equivalents	$ 64,772	$ 27,269
Accounts receivable, net	262,949	165,768
Materials and supplies	32,389	14,445
Prepaid expenses and other	33,586	13,332
Deferred income tax assets, net	71,556	19,385
Total current assets	465,252	240,199
PROPERTY AND EQUIPMENT, net	3,396,295	1,643,589
GOODWILL	634,953	160,277
INTANGIBLE ASSETS, net	670,206	230,628
DEFERRED INCOME TAX ASSETS, net	2,396	2,342
OTHER ASSETS, net	57,013	17,122
Total assets	5,226,115	2,294,157
CURRENT LIABILITIES: [Abstract]
Current portion of long-term debt	87,569	57,168
Accounts payable	232,121	134,081
Accrued expenses	93,971	69,097
Deferred income tax liabilities, net	3,083	925
Total current liabilities	416,744	261,271
LONG-TERM DEBT, less current portion	1,770,566	569,026
DEFERRED INCOME TAX LIABILITIES, net	862,734	285,780
DEFERRED ITEMS - grants from outside parties	228,579	198,824
OTHER LONG-TERM LIABILITIES	47,506	18,622
COMMITMENTS AND CONTINGENCIES	0	0
SERIES A-1 PREFERRED STOCK	399,524	0
EQUITY: [Abstract]
Additional paid-in capital	866,609	385,473
Retained earnings	789,727	741,669
Accumulated other comprehensive income	47,271	37,895
Treasury stock, at cost	(209,266)	(204,952)
Total Genesee & Wyoming Inc. stockholders' equity	1,494,937	960,634
Noncontrolling interest	5,525	0
Total equity	1,500,462	960,634
Total liabilities and equity	5,226,115	2,294,157
Class A [Member]
EQUITY: [Abstract]
Common Stock	579	527
Class B [Member]
EQUITY: [Abstract]
Common Stock	$ 17	$ 22