Segment Information (Details) $ in Thousands	3 Months Ended	12 Months Ended
Apr. 02, 2016 USD ($) Segment	Mar. 28, 2015 USD ($)	Dec. 26, 2015 USD ($) Segment
Segment Information [Abstract]
Number of reportable segments \| Segment	3		2
Summary of segment information [Abstract]
Net sales	$ 532,809	$ 537,242
Cost of goods sold	446,642	460,834
Depreciation and amortization	8,920	7,853
Selling, general, and administrative expense	35,780	32,831
Operating income	41,467	35,724
Interest expense	(1,848)	(2,076)
Other income, net	245	105
Income before income taxes	39,864	33,753
Segment assets	1,361,020		$ 1,338,801
Piping Systems [Member]
Summary of segment information [Abstract]
Segment assets	815,400		811,343
Industrial Metals [Member]
Summary of segment information [Abstract]
Segment assets	193,662		174,897
Climate [Member]
Summary of segment information [Abstract]
Segment assets	41,172		39,876
General Corporate [Member]
Summary of segment information [Abstract]
Segment assets	310,786		$ 312,685
Operating Segments [Member] \| Piping Systems [Member]
Summary of segment information [Abstract]
Net sales	368,890	361,482
Cost of goods sold	313,792	312,690
Depreciation and amortization	5,649	5,187
Selling, general, and administrative expense	18,290	17,346
Operating income	31,159	26,259
Operating Segments [Member] \| Industrial Metals [Member]
Summary of segment information [Abstract]
Net sales	134,521	151,036
Cost of goods sold	109,229	127,724
Depreciation and amortization	2,135	1,655
Selling, general, and administrative expense	3,245	2,698
Operating income	19,912	18,959
Operating Segments [Member] \| Climate [Member]
Summary of segment information [Abstract]
Net sales	30,706	25,811
Cost of goods sold	23,705	21,267
Depreciation and amortization	599	425
Selling, general, and administrative expense	2,523	1,854
Operating income	3,879	2,265
Corporate and Eliminations [Member]
Summary of segment information [Abstract]
Net sales	(1,308)	(1,087)
Cost of goods sold	(84)	(847)
Depreciation and amortization	537	586
Selling, general, and administrative expense	11,722	10,933
Operating income	$ (13,483)	$ (11,759)

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.18)
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