Commitments And Contingencies (Components Of Lease Expense) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Commitments And Contingencies [Abstract]
Operating lease expense	$ 20,806
Variable lease expense	824	[1]
Total lease expense	$ 21,630

[1] Represents amounts incurred in excess of the minimum payments required for the handling and unloading of railcars for a certain land lease, offset by railcar lease abatements provided by the lessor when railcars are out of service during periods of maintenance or upgrade.