Income Taxes (Reconciliation Of Unrecognized Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit as of January 1	$ 15,209	$ 16,067	$ 16,342
Gross increases-tax positions in prior period	905	983	64
Gross decreases-tax positions in prior period	(765)	(2,502)	(850)
Gross increases-tax positions in current period	3,757	2,725	4,064
Reductions due to a lapse of the applicable statute of limitations	(847)	(927)	(2,808)
Changes due to currency fluctuation	1,414
Changes due to currency fluctuation		(348)	(653)
Settlements	(16)	(789)	(92)
Unrecognized tax benefit as of December 31	$ 19,657	$ 15,209	$ 16,067

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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