Revenue (Disaggregation Of Revenue) (Details) - Revenue from Contract with Customer [Member]	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total net sales	100.00%	100.00%
Construction
Disaggregation of Revenue [Line Items]
Total net sales	57.80%	58.20%
CIG
Disaggregation of Revenue [Line Items]
Total net sales	26.60%	26.10%
Industrial & Utility
Disaggregation of Revenue [Line Items]
Total net sales	15.60%	15.70%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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