Business and Customers (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of railroads operated	116
Number of operating regions	11
Miles of owned and leased track	15,600
Miles under contractual track access arrangements	3,300
Number of employees	5,200
Customers served	2,000
Ports operated	37
Customer Concentration Risk [Member]
10 largest customers % of revenues	24.00%	24.00%	31.00%
Australia [Member]
Track miles	1,400