Changes in Operations (Details 3)	3 Months Ended		9 Months Ended		1 Months Ended			3 Months Ended		1 Months Ended
	Sep. 30, 2012 USD ($)	Sep. 30, 2011 USD ($)	Sep. 30, 2012 USD ($)	Sep. 30, 2011 USD ($)	Jul. 31, 2012 Arrium Limited [Member] tons	Jul. 17, 2012 Arrium Limited [Member] Narrow Gauge Locomotives And Wagons [Member] USD ($)	Jul. 17, 2012 Arrium Limited [Member] Narrow Gauge Locomotives And Wagons [Member] AUD	Sep. 30, 2012 Cook [Member] USD ($)	Sep. 30, 2012 Cook [Member] AUD	Jun. 30, 2012 Alice Springs Intermodal And Freight Terminal [Member] USD ($)	Jun. 30, 2012 Alice Springs Intermodal And Freight Terminal [Member] AUD	Sep. 30, 2012 Alice Springs Intermodal And Freight Terminal [Member] USD ($)	Sep. 30, 2012 Alice Springs Intermodal And Freight Terminal [Member] AUD
Purchase of property and equipment			$ 170,529,000	$ 106,386,000						$ 9,200,000	9,000,000
Stamp duty												600,000	500,000
Proceeds from disposition of property and equipment			13,673,000	4,054,000				4,100,000	4,000,000
Gain/(loss) on sale of property and equipment	3,018,000	610,000	10,447,000	2,708,000				1,300,000	1,300,000
EPS impact from gain on sale of property and equpment								$ 0.03
Tons per year of product shipped					2,700,000
Other commitment						$ 62,300,000	60,000,000