Accrued Liabilities (Schedule Of Accrued Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accrued Liabilities, Current [Abstract]
Accrued employee compensation and related expenses	$ 106,191	$ 127,174
Accrued expenses	67,265	86,296
Accrued customer incentives and refund obligations	63,149	63,079
Accrued taxes	55,690	31,108
Current lease liabilities	16,473	15,281
Accrued liabilities	$ 308,768	$ 322,938