Cash Flows (Summary Of Non-Cash Activities And Other Supplemental Data) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Noncash Investing and Financing Items [Abstract]
Increase in capital lease obligations	$ 0	$ 10,983
Treasury Stock Not Yet Settled	5,988	0
Capital expenditures incurred but not yet paid	3,362	2,722
Cash interest paid	8,605	46,436
Income taxes paid, net	$ 7,498	$ 5,600