Other Operating Expenses/(Income) (Schedule Of Other Operating Expenses/(Income)) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Total other operating expenses/(income)	$ 12,207	$ 78	$ (28,935)	$ 9,001
CARES Act Grant [Member]
Total other operating expenses/(income)	8,805		(32,184)
Litigation Settlement [Member]
Total other operating expenses/(income)	3,095		3,095	6,000
Loss On Disposal Of Fixed Assets [Member]
Total other operating expenses/(income)	$ 307	$ 78	$ 154	735
Transportation Equipment Held For Sale [Member]
Total other operating expenses/(income)				$ 2,266