Earnings Per Share (Details) (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 25, 2011	Jun. 26, 2010	Jun. 25, 2011	Jun. 26, 2010
Basic EPS
Net earnings attributable to Valmont Industries, Inc, basic	$ 45,827	$ 17,115	$ 71,436	$ 33,578
Shares outstanding basic (in shares)	26,333	26,087	26,302	26,059
Per share amount basic (in dollars per share)	$ 1.74	$ 0.66	$ 2.72	$ 1.29
Dilutive Effect of Stock Options
Net earnings attributable to Valmont Industries, Inc, dilutive effect of stock options
Dilutive effect of stock options number of shares (in shares)	252	361	259	375
Dilutive effect of stock options (in dollars per share)	$ (0.02)	$ (0.01)	$ (0.03)	$ (0.02)
Diluted EPS
Net earnings attributable to Valmont Industries, Inc, diluted	$ 45,827	$ 17,115	$ 71,436	$ 33,578
Shares outstanding dilutive (in shares)	26,585	26,448	26,561	26,434
Per share amount diluted (in dollars per share)	$ 1.72	$ 0.65	$ 2.69	$ 1.27
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)	16,828	455,153	16,828	455,153

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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