GOODWILL AND INTANGIBLE ASSETS (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2013	Dec. 29, 2012
Webforge
Non-amortized intangible assets
Carrying value of trade names	$ 17,787	$ 17,411
Newmark
Non-amortized intangible assets
Carrying value of trade names	11,111	11,111
Ingal EPS/Ingal Civil Products
Non-amortized intangible assets
Carrying value of trade names	9,387	9,189
Donhad
Non-amortized intangible assets
Carrying value of trade names	7,082	6,932
Pure Metal Galvanizing
Non-amortized intangible assets
Carrying value of trade names	1,888	2,022
PiRod
Non-amortized intangible assets
Carrying value of trade names	1,750	1,750
Industrial Galvanizers
Non-amortized intangible assets
Carrying value of trade names	4,117	4,030
Other
Non-amortized intangible assets
Carrying value of trade names	11,047	7,247
Trade names
Non-amortized intangible assets
Carrying value of trade names	$ 64,169	$ 59,692