Equity Investment RailAmerica Condensed Statemetn of Comprehensive Income(Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended			3 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 28, 2012 RailAmerica [Member]	Dec. 31, 2012 RailAmerica [Member]
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Unamortized (Gain) Loss Arising During Period, Tax									$ (166)	$ (24)	$ 196		$ 53
NET INCOME	9,021	(19,567)	36,363	22,241	33,275	32,942	31,145	22,122				15,806
OTHER COMPREHENSIVE INCOME/(LOSS):
Foreign currency translation adjustment									5,616	(3,511)	21,877	(2,150)
Actuarial gain associated with pension and postretirement benefit plans, net of tax provision of $53									(293)	(42)	344	166
Other comprehensive loss									(9,376)	2,219	(20,631)	(1,984)
COMPREHENSIVE INCOME									$ 61,809	$ 117,265	$ 101,891	$ 13,822