Description Of Business And Segment Reporting (Summary Of Capital Expenditures) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total capital expenditures	$ 49,166	$ 53,119	$ 14,914
Segment [Member]
Segment Reporting Information [Line Items]
Total capital expenditures	49,023	52,989	14,310
Corporate [Member]
Segment Reporting Information [Line Items]
Total capital expenditures	$ 143	$ 130	$ 604