Accounts Receivable (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2012 Accounts receivable - trade [Member]	Dec. 31, 2011 Accounts receivable - trade [Member]	Dec. 31, 2012 Accounts receivable - grants [Member]	Dec. 31, 2011 Accounts receivable - grants [Member]	Dec. 31, 2010 Accounts receivable - grants [Member]	Dec. 31, 2012 Accounts receivable insurance claims [Member]	Dec. 31, 2011 Accounts receivable insurance claims [Member]	Dec. 28, 2012 RailAmerica [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total accounts receivable	$ 265,642	$ 168,575			$ 214,163	$ 130,486	$ 25,036	$ 20,753	$ 17,000	$ 26,443	$ 17,336
Less: allowance for doubtful accounts	(2,693)	(2,807)	(3,079)	(3,764)
Accounts receivable, net	$ 262,949	$ 165,768										$ 91,400