Leases (Summary of Amounts Recognized in Condensed Consolidated Balance Sheet) (Details) - USD ($) $ in Thousands		Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Assets
Operating lease assets		$ 74,073	$ 0	$ 0
Finance lease assets, property, plant and equipment, net		24,099
Total leased assets		100,219
Liabilities
Current operating leases		25,672
Non-current operating leases		48,401	0	0
Total operating lease liabilities		74,073
Current finance leases	[1]	16,990	0	0
Non-current finance leases	[1]	21,940	$ 0	$ 0
Total finance lease liabilities		38,930
Total lease liabilities		113,003
Rail
Assets
Finance lease assets, property, plant and equipment, net		$ 2,047

[1] See Note 14, Leases, for additional information. June 30, 2019 balances include the former build-to-suit lease that was reclassed from other current liabilities and other long-term liabilities as a result of the new lease standard.