EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 25, 2010	Dec. 26, 2009
Basic EPS
Net earnings attributable to Valmont Industries, Inc, basic	$ 228,308	$ 94,379	$ 150,562
Shares outstanding basic (in shares)	26,329	26,100	25,951
Per share amount basic (in dollars per share)	$ 8.67	$ 3.62	$ 5.80
Dilutive Effect of Stock Options
Dilutive effect of stock options number of shares	221	322	338
Net earnings attributable to Valmont Industries, Inc, dilutive effect of stock options	221	322	338
Dilutive effect of stock options (in dollars per share)	$ 0.07	$ 0.05	$ 0.07
Diluted EPS
Net earnings attributable to Valmont Industries, Inc, diluted	$ 228,308	$ 94,379	$ 150,562
Shares outstanding dilutive (in shares)	26,550	26,422	26,289
Per share amount diluted (in dollars per share)	$ 8.60	$ 3.57	$ 5.73
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)	20,000	8,000	255,000

The amount resulting from the "as if" assumption that stock options or restrictive stock units were exercised for purposes of computing the dilutive effect of convertible securities.

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