v3.8.0.1

Significant Accounting Policies - Narrative (Details) | 12 Months Ended
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Dec. 31, 2017 USD ($) segment customer | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Significant Accounting Policies [Line Items] |  |  |
Number of business segments | segment | 1 |  |
Percentage of copper use in relation to cost of goods sold | 69.70% | 65.20% | 72.10%
Shipping and handling cost | $ 26,200,000 | $ 24,100,000 | $ 22,700,000
Certificates of deposit | $ 30,200,000 | $ 0 |
Buildings and Improvements | Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 15 years |  |
Buildings and Improvements | Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 39 years |  |
Machinery and Equipment | Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 3 years |  |
Machinery and Equipment | Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 20 years |  |
Furniture and Fixtures | Minimum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 3 years |  |
Furniture and Fixtures | Maximum |  |  |
Significant Accounting Policies [Line Items] |  |  |
Estimated useful lives of property plant and equipment (in years) | 15 years |  |
Customer Concentration Risk | Sales Revenue, Net |  |  |
Significant Accounting Policies [Line Items] |  |  |
Customer concentration risk, number of customers | customer | 2 |  |

X
- Definition A savings certificate entitling the Entity (that is, bearer) to receive interest at an established maturity date, based upon a fixed interest rate. A certificate of deposit may be issued in any denomination. Certificates of deposit are generally issued by commercial banks and, therefore, insured by the FDIC (up to the prescribed limit). Certificates of deposit generally restrict holders from withdrawing funds on demand without the incurrence of penalties. Generally, only certificates of deposit with original maturities of three months or less qualify as cash equivalents. Original maturity means original maturity to the entity holding the investment. As a related example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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- Definition Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18780-107790 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 45 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=68080631&loc=d3e61069-111654 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 45 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=68075638&loc=d3e60635-111653 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=84158767&loc=d3e18726-107790 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 45 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82851458&loc=d3e221937-122793 + Details
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- Definition Percentage of copper use in relation to cost of goods sold. + References No definition available. + Details
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