Earnings per Share Basic and Diluted EPS (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Numerator [Line items]
Net income attributable to Genesee & Wyoming Inc.	$ 38,706	$ 75,098
Denominators [Line Items]
Weighted average Class A common shares outstanding-Basic	56,368	61,918
Weighted average Class B common shares outstanding	498	701
Dilutive effect of employee stock-based awards	266	268
Weighted average shares - Diluted	57,132	62,887
Earnings per common share [Line Items]
Basic earnings per common share attributable to Genesee & Wyoming Inc. common stockholders	$ 0.69	$ 1.21
Diluted earnings per common share attributable to Genesee & Wyoming Inc. common stockholders	$ 0.68	$ 1.19

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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