Changes in Operations United States - HOG (Details) - Heart of Georgia Railroad [Member] $ in Millions		9 Months Ended
May 31, 2017 USD ($)	Sep. 30, 2018 mile carload
Business Acquisition, Effective Date of Acquisition	May 31, 2017
Business Acquisition, Percentage of Voting Interests Acquired	100.00%
Cash consideration	$ 5.6
Contingent consideration	$ 5.7
Track Miles Leased \| mile		219
Annual carloads transported \| carload		7,000

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Track Miles Leased

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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