Income Taxes Components of Net Deferred Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Deferred Tax Assets, Gross [Abstract]
Accruals and reserves not deducted for tax purposes until paid	$ 15,824	$ 4,290
Net operating loss carryforwards	52,863	1,306
Capital loss carryforward	0	5,251
Interest rate swaps	7	2,547
Nonshareholder contributions	4,799	1,622
Deferred compensation	2,175	2,473
Postretirement benefits	2,328	801
Share-based compensation	11,328	4,358
Foreign tax credit	1,964	1,964
Track maintenance credit	129,486	38,238
Alternative minimum tax credit	1,356
Other	451	87
Total deferred tax assets	222,581	62,937
Valuation allowance	(8,613)	(5,251)
Deferred Tax Liabilities, Net [Abstract]
Property basis difference	(1,003,990)	(321,365)
Other	(1,843)	(1,299)
Net deferred tax liabilities	$ (791,865)	$ (264,978)