Property and Equipment and Leases Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) rail_car locomotive	Dec. 31, 2014 USD ($) rail_car locomotive	Dec. 31, 2013 USD ($)
Operating Leased Assets [Line Items]
Leased railcars | rail_car	21,819	18,583
Leased locomotives | locomotive	333	162
Revenues from leased railroads as a percentage of total operating revenues	7.40%
Revenues from leased railroads subject to expiration in each of the next 10 years as a percentage of annual total operating revenues	2.00%
Equipment [Member]
Operating Leased Assets [Line Items]
Operating lease expense	$ 82,853	$ 29,462	$ 32,050
Real property [Member]
Operating Leased Assets [Line Items]
Operating lease expense	11,715	8,361	8,062
Trackage rights [Member]
Operating Leased Assets [Line Items]
Operating lease expense	$ 78,140	$ 53,783	$ 50,911