Changes in Operations United States RailAmerica (Details) (USD $)	3 Months Ended		9 Months Ended		0 Months Ended	3 Months Ended	9 Months Ended	0 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Oct. 02, 2012 RailAmerica [Member] employee state railroad province mile	Dec. 28, 2012 RailAmerica [Member]	Sep. 30, 2012 RailAmerica [Member]	Oct. 02, 2012 Common stock and TEUs [Member] RailAmerica [Member]	Oct. 02, 2012 The Carlyle Group [Member] Series A-1 Preferred Stock [Member] RailAmerica [Member]	Sep. 30, 2012 Contingent forward sale contract [Member]	Sep. 30, 2012 Contingent forward sale contract [Member]	Dec. 31, 2013 Scenario, Forecast [Member] RailAmerica [Member]
Business Acquisition [Line Items]
Percentage of outstanding shares acquired					100.00%
RailAmerica outstanding common stock as of October 1, 2012					49,934,000
Cash purchase price per share					$ 27.50
Equity purchase price					$ 1,373,184,000
Payment of RailAmerica's outstanding term loan and revolving credit facility					659,198,000
Cash consideration					2,032,382,000
Impact of pre-acquisition share-based awards					9,400,000
Total consideration					2,041,782,000
Refinancing of debt for business acquisition					1,200,000,000
Amount of debt used to fund business acquisition					1,900,000,000
Proceeds from issuance or sale of equity			0	234,361,000				475,500,000
Proceeds from issuance of preferred stock									350,000,000
Contingent forward sale contract mark-to-market expense	0	50,106,000	0	50,106,000						50,100,000	50,106,000
Contingent forward sale contract liability										50,106,000	50,106,000
Number of employees acquired					2,000
Number of railroads acquired					45
Track miles acquired					7,100
Number of U.S states in which entity operates					28
Canadian provinces operated in					3
Income/(loss) from equity method investments						15,600,000
Other comprehensive income/(loss) from equity method investment						(2,000,000)
Reduction in net cash paid for the acquisition						21,800,000
Measurement period adjustment to the allocation of fair values to property and equipment							10,700,000
Measurement period adjustment to the allocation of fair values to intangible assets							(29,900,000)
Measurement period adjustment to the allocation of fair values to deferred income tax liabilities, net							(11,400,000)
Measurement period adjustment to the allocation of fair values to noncontrolling interest							(5,000,000)
Measurement period adjustment to the allocation of fair values to other assets, net							1,300,000
Measurement period adjustment to the allocation of fair values to goodwill							(1,500,000)
Additional depreciation and amortization expense as a result of the measurement period adjustment to the allocation of fair values							$ 3,000,000					$ 4,000,000