Description Of Business And Segment Reporting (Summary Of Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total capital expenditures	$ 47,722	$ 56,827	$ 76,708
Segment [Member]
Segment Reporting Information [Line Items]
Total capital expenditures	47,555	56,795	76,300
Corporate [Member]
Segment Reporting Information [Line Items]
Total capital expenditures	$ 167	$ 32	$ 408