Significant Accounting Policies Insurance (Details) In Millions, unless otherwise specified	Dec. 31, 2014 Liability policies [Member] USD ($)	Dec. 31, 2014 Property policies [Member] USD ($)	Oct. 02, 2012 RailAmerica [Member] Liability policies [Member] USD ($)	Oct. 02, 2012 RailAmerica [Member] Property policies [Member] USD ($)	Dec. 31, 2014 Australia [Member] Property policies [Member] AUD
Supplemental Information for Property, Casualty Insurance Underwriters [Line Items]
Self-insured retention, maximum per incident	$ 2.5	$ 1.0			2.5
Prior self-insured retention, maximum per incident			$ 4.0	$ 1.5