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Segment Information - Net Sales by Major Product Line (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Apr. 01, 2017
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | $ 644,359 | $ 582,891
Tube and fittings [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 358,091 | 308,366
Brass rod and forgings [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 136,548 | 114,180
OEM components, tube and assemblies [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 58,192 | 79,465
Valves and plumbing specialties [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 65,811 | 58,438
Other products [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 25,717 | 22,442
Operating Segments [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 430,964 | 398,775
Operating Segments [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 177,332 | 149,837
Operating Segments [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 36,063 | 34,279
Operating Segments [Member] | Tube and fittings [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 358,091 | 308,366
Operating Segments [Member] | Tube and fittings [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Tube and fittings [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Brass rod and forgings [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Brass rod and forgings [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 136,548 | 114,180
Operating Segments [Member] | Brass rod and forgings [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | OEM components, tube and assemblies [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 7,062 | 31,971
Operating Segments [Member] | OEM components, tube and assemblies [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 15,067 | 13,215
Operating Segments [Member] | OEM components, tube and assemblies [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 36,063 | 34,279
Operating Segments [Member] | Valves and plumbing specialties [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 65,811 | 58,438
Operating Segments [Member] | Valves and plumbing specialties [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Valves and plumbing specialties [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Other products [Member] | Piping Systems [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Operating Segments [Member] | Other products [Member] | Industrial Metals [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 25,717 | 22,442
Operating Segments [Member] | Other products [Member] | Climate [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales | 0 | 0
Intersegment Sales [Member] |  |
Revenues from External Customers and Long-Lived Assets [Line Items] |  |
Net sales |  |

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