Revenue Recognition (Comparison Of Geographic Revenues) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,327,576	$ 1,265,052	$ 1,231,661
U.S. [Member]
Disaggregation of Revenue [Line Items]
Total revenues	851,299	804,647	772,586
EMEA [Member]
Disaggregation of Revenue [Line Items]
Total revenues	231,686	214,204	206,975
CHINA
Disaggregation of Revenue [Line Items]
Total revenues	99,727	113,048	119,291
Other [Member]
Disaggregation of Revenue [Line Items]
Total revenues	$ 144,864	$ 133,153	$ 132,809