ACQUISITIONS (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended			3 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended		1 Months Ended
	Mar. 30, 2013	Mar. 29, 2014	Dec. 28, 2013	Mar. 29, 2014 Valmont SM, Locker, and Armorflex acquisitions	Mar. 03, 2014 Valmont SM item	Mar. 29, 2014 Valmont SM	Feb. 05, 2013 Locker	Feb. 05, 2013 Locker Maximum	Dec. 28, 2013 Armorflex International Ltd.
Acquisitions
Ownership percentage acquired					90.00%		100.00%		100.00%
Annual sales					$ 190,000
Number of manufacturing locations operated					2
Cash acquired					56		116
Cash paid for acquisition					120,483		53,152		10,000
Fair value of contingent consideration					0			7,911
Fair values of the assets acquired and liabilities assumed
Current assets					73,421
Property, plant and equipment					69,438
Intangible assets					59,110				3,792
Goodwill		355,844	349,632		4,885				6,864
Total fair value of assets acquired					206,854
Current liabilities					50,953
Deferred income taxes					17,245
Intercompany note payable					37,448
Long-term debt					8,941
Non-controlling interests					9,232
Total fair value of liabilities assumed					123,819
Net assets acquired					83,035
Net sales and net earnings included in Consolidated Statements of Earnings
Net sales included in Consolidated Statements of Earnings				34,581		17,304
Net earnings included in Consolidated Statements of Earnings				1,686		1,178
Period at the end of which contingent consideration is to be paid							2 years
Present value of the potential additional purchase price							7,178
Pro forma results of operations
Net sales	867,855
Net earnings	$ 79,433
Earnings per share-diluted	$ 2.96