Cash Flows (Summary Of Non-Cash Activities And Other Supplemental Data) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Noncash Investing and Financing Items [Abstract]
Increase in capital lease obligations	$ 0	$ 10,983
Treasury stock not yet settled	8,987	0
Exercise of RLJE warrants	5,001	0
Capital expenditures incurred but not yet paid	2,412	2,101
Cash interest paid	56,832	69,449
Income taxes paid, net	$ 124,474	$ 75,450