EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 29, 2014	Mar. 30, 2013
Basic EPS
Net earnings attributable to Valmont Industries, Inc, basic	$ 55,980	$ 77,569
Shares outstanding basic	26,715	26,583
Per share amount basic (in dollars per share)	$ 2.10	$ 2.92
Dilutive Effect of Stock Options
Dilutive effect of stock options number of shares	235	276
Dilutive effect of stock options (in dollars per share)	$ (0.02)	$ (0.03)
Diluted EPS
Net earnings attributable to Valmont Industries, Inc, diluted	$ 55,980	$ 77,569
Shares outstanding dilutive	26,950	26,859
Per share amount diluted (in dollars per share)	$ 2.08	$ 2.89
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	0