Cash Flows (Summary Of Non-Cash Activities And Other Supplemental Data) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Capital expenditures incurred but not yet paid	$ 2,216	$ 6,070
Treasury stock not yet settled	0	9,980
Cash interest paid	28,235	25,634
Income taxes paid, net	$ 6,426	$ 6,243