Segment and Geographic Area Information North American & European and Australian Operations (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013 region	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Number of operating regions									11
Operating revenues	$ 391,674,000	$ 401,388,000	$ 400,741,000	$ 375,208,000	$ 227,316,000	$ 222,745,000	$ 217,419,000	$ 207,436,000	$ 1,569,011,000	$ 874,916,000	$ 829,096,000
Income from operations	94,830,000	101,741,000	107,417,000	76,200,000	33,660,000	52,875,000	62,473,000	41,314,000	380,188,000	190,322,000	191,779,000
Depreciation and amortization									141,644,000	73,405,000	66,481,000
Interest expense									67,894,000	62,845,000	38,617,000
Interest income									3,971,000	3,725,000	3,243,000
Contingent forward sale contract mark-to-market expense						50,100,000			0	50,106,000	0
Provision for income taxes									46,296,000	46,402,000	38,531,000
Income from equity investment in RailAmerica, net									0	15,557,000	0
Expenditures for additions to property & equipment, net of grants from outside parties									215,405,000	192,062,000	156,026,000
North American & European Operations [Member]
Segment Reporting Information [Line Items]
Operating revenues									1,243,847,000	585,893,000	557,621,000
Income from operations									284,122,000	115,387,000	129,646,000
Depreciation and amortization									114,542,000	50,156,000	47,218,000
Interest expense									52,740,000	45,996,000	23,171,000
Interest income									3,631,000	3,219,000	2,950,000
Contingent forward sale contract mark-to-market expense										50,106,000
Provision for income taxes									24,038,000	28,451,000	26,181,000
Income from equity investment in RailAmerica, net										15,557,000
Expenditures for additions to property & equipment, net of grants from outside parties									163,545,000	69,636,000	59,383,000
Australian Operations [Member]
Segment Reporting Information [Line Items]
Operating revenues									325,164,000	289,023,000	271,475,000
Income from operations									96,066,000	74,935,000	62,133,000
Depreciation and amortization									27,102,000	23,249,000	19,263,000
Interest expense									15,154,000	16,849,000	15,446,000
Interest income									340,000	506,000	293,000
Contingent forward sale contract mark-to-market expense										0
Provision for income taxes									22,258,000	17,951,000	12,350,000
Income from equity investment in RailAmerica, net										0
Expenditures for additions to property & equipment, net of grants from outside parties									$ 51,860,000	$ 122,426,000	$ 96,643,000