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Segment Information - Net Sales by Major Product Line (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 30, 2017 | Dec. 31, 2016 | Dec. 26, 2015
Revenue from External Customer [Line Items] |  |  |
Net sales | $ 2,266,073 | $ 2,055,622 | $ 2,100,002
Tube and Fittings [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Net sales | 1,260,105 | 1,072,242 | 1,053,761
Brass Rod and Forgings [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Net sales | 450,063 | 371,237 | 436,456
OEM Components, Tube & Assemblies [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Net sales | 272,567 | 327,327 | 342,651
Valves and Plumbing Specialties [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Net sales | 200,409 | 209,217 | 198,012
Other [Member] |  |  |
Revenue from External Customer [Line Items] |  |  |
Net sales | $ 82,929 | $ 75,599 | $ 69,122

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- Definition Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.1(a)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
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