Property And Equipment (Schedule Of Components Of Property And Equipment) (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 1,460,544	$ 1,331,884
Less: accumulated depreciation and amortization	(567,027)	(530,194)
Property and equipment, net	893,517	801,690
Plant Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	1,000,820	940,363
Building and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	180,713	170,813
Land and Land Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	83,403	86,909
Railroad Track and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	32,971	34,637
Construction-in-Progress [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	111,745	48,378
Computer Hardware And Software [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	19,927	20,477
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	3,356	3,797
Leasehold Improvements And Other [Member]
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 27,609	$ 26,510