GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 28, 2015	Mar. 29, 2014
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net earnings	$ 31,507us-gaap_ProfitLoss	$ 56,563us-gaap_ProfitLoss
Foreign currency translation adjustments:
Unrealized translation gain (loss)	(58,178)	11,637
Unrealized gain/(loss) on cash flow hedge:
Gain on cash flow hedges	294
Amortization cost included in interest expense	18	100
Actuarial gain (loss) in defined benefit pension plan liability		(233)
Other comprehensive income (loss)	(57,866)	11,504
Comprehensive income (loss)	(26,359)	68,067
Comprehensive loss (income) attributable to noncontrolling interests	1,327	88
Comprehensive income (loss) attributable to Valmont Industries, Inc.	(25,032)us-gaap_ComprehensiveIncomeNetOfTax	68,155us-gaap_ComprehensiveIncomeNetOfTax
Parent
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net earnings	30,739	55,980
Unrealized gain/(loss) on cash flow hedge:
Gain on cash flow hedges	92
Amortization cost included in interest expense	18	100
Equity in other comprehensive income	(55,881)	12,075
Other comprehensive income (loss)	(55,771)	12,175
Comprehensive income (loss)	(25,032)	68,155
Comprehensive income (loss) attributable to Valmont Industries, Inc.	(25,032)	68,155
Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net earnings	9,944	15,684
Foreign currency translation adjustments:
Unrealized translation gain (loss)	(8,888)	1,189
Unrealized gain/(loss) on cash flow hedge:
Other comprehensive income (loss)	(8,888)	1,189
Comprehensive income (loss)	1,056	16,873
Comprehensive income (loss) attributable to Valmont Industries, Inc.	1,056	16,873
Non-Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net earnings	13,050	9,687
Foreign currency translation adjustments:
Unrealized translation gain (loss)	(49,290)	10,448
Unrealized gain/(loss) on cash flow hedge:
Gain on cash flow hedges	202
Actuarial gain (loss) in defined benefit pension plan liability		(233)
Other comprehensive income (loss)	(49,698)	10,215
Comprehensive income (loss)	(36,038)	19,902
Comprehensive loss (income) attributable to noncontrolling interests	1,327	88
Comprehensive income (loss) attributable to Valmont Industries, Inc.	(34,711)	19,990
Eliminations
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net earnings	(22,226)	(24,788)
Unrealized gain/(loss) on cash flow hedge:
Equity in other comprehensive income	55,881	(12,075)
Other comprehensive income (loss)	55,881	(12,075)
Comprehensive income (loss)	33,655	(36,863)
Comprehensive income (loss) attributable to Valmont Industries, Inc.	$ 33,655	$ (36,863)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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