Revenue - Disaggregation of Revenue (Details) - Revenue from Contract with Customer [Member]	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total net sales	100.00%	100.00%	100.00%	100.00%
Construction
Disaggregation of Revenue [Line Items]
Total net sales	60.80%	60.40%	60.30%	59.40%
Industrial & Utility
Disaggregation of Revenue [Line Items]
Total net sales	20.30%	20.90%	20.60%	19.70%
CIG
Disaggregation of Revenue [Line Items]
Total net sales	18.90%	18.70%	19.10%	20.90%

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
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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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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