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Retirement Plans And Postretirement Benefits (Fair Asset Values Of Plan Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
U.S.
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 109,845	$ 100,905	$ 93,897
U.S. | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,094	1,502
U.S. | Collective Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107,751	99,403
U.S. | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,094	1,502
U.S. | Fair Value, Inputs, Level 1 [Member] | Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,094	1,502
U.S. | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107,751	99,403
U.S. | Fair Value, Inputs, Level 2 [Member] | Collective Trusts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	107,751	99,403
Foreign
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,618	11,871	$ 11,293
Foreign | Foreign Government Debt [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	831	729
Foreign | Fixed Insurance Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,787	11,142
Foreign | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	831	729
Foreign | Fair Value, Inputs, Level 2 [Member] | Foreign Government Debt [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	831	729
Foreign | Fair Value, Inputs, Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,787	11,142
Foreign | Fair Value, Inputs, Level 3 [Member] | Fixed Insurance Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 12,787	$ 11,142

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- Definition

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+ References

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- Definition

Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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