EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Basic EPS
Net earnings attributable to Valmont Industries, Inc, basic	$ 89,563	$ 59,980	$ 167,132	$ 112,305
Shares outstanding basic	26,648	26,467	26,615	26,432
Per share amount basic (in dollars per share)	$ 3.36	$ 2.27	$ 6.28	$ 4.25
Dilutive Effect of Stock Options
Dilutive effect of stock options number of shares	262	291	269	286
Dilutive effect of stock options (in dollars per share)	$ (0.03)	$ (0.03)	$ (0.06)	$ (0.05)
Diluted EPS
Net earnings attributable to Valmont Industries, Inc, diluted	$ 89,563	$ 59,980	$ 167,132	$ 112,305
Shares outstanding dilutive	26,910	26,758	26,884	26,718
Per share amount diluted (in dollars per share)	$ 3.33	$ 2.24	$ 6.22	$ 4.20
Antidilutive Securities
Outstanding stock options with exercise prices exceeding the market price of common stock, excluded from the computation of diluted earnings per share (in shares)	1,172		1,172	0

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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