Other Current and Long-Term Assets (Schedule Of Other Long-term Assets) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Other Current and Long-Term Assets [Abstract]
Investment in long-term product supply arrangements	$ 9,637	$ 10,978
Customer acquisition costs, net	59,109	50,309
Other assets	35,494	36,321
Deferred income taxes	6,701	5,707
Other long-term assets	$ 110,941	$ 103,315