GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013	Sep. 29, 2012
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	$ 778,032	$ 729,839	$ 2,476,321	$ 2,214,504
Cost of sales	552,468	537,437	1,753,917	1,636,393
Gross profit	225,564	192,402	722,404	578,111
Selling, general and administrative expenses	115,663	102,020	350,048	307,559
Operating income	109,901	90,382	372,356	270,552
Other income (expense):
Interest expense	(8,149)	(8,429)	(24,364)	(23,657)
Interest income	1,560	2,093	4,765	6,081
Other	(584)	1,307	1,095	907
Total other income (expenses)	(7,173)	(5,029)	(18,504)	(16,669)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	102,728	85,353	353,852	253,883
Income tax expense (benefit):
Current	40,458	27,928	127,328	90,942
Deferred	3,454	519	(1,275)	(3,937)
Total income tax expense (benefit)	43,912	28,447	126,053	87,005
Earnings before equity in earnings of nonconsolidated subsidiaries	58,816	56,906	227,799	166,878
Equity in earnings of nonconsolidated subsidiaries	75	1,536	548	5,311
Net earnings	58,891	58,442	228,347	172,189
Less: Earnings attributable to noncontrolling interests	(2,402)	(1,711)	(4,726)	(3,153)
Net earnings attributable to Valmont Industries, Inc.	56,489	56,731	223,621	169,036
Parent
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	331,525	301,667	1,174,955	1,014,150
Cost of sales	238,692	226,539	837,321	743,608
Gross profit	92,833	75,128	337,634	270,542
Selling, general and administrative expenses	51,621	41,747	157,367	128,781
Operating income	41,212	33,381	180,267	141,761
Other income (expense):
Interest expense	(7,724)	(8,215)	(23,115)	(23,470)
Interest income	18	15	33	29
Other	1,422	883	3,224	1,888
Total other income (expenses)	(6,284)	(7,317)	(19,858)	(21,553)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	34,928	26,064	160,409	120,208
Income tax expense (benefit):
Current	19,473	8,096	65,472	44,644
Deferred	(4,969)	(1,063)	(7,473)	(3,832)
Total income tax expense (benefit)	14,504	7,033	57,999	40,812
Earnings before equity in earnings of nonconsolidated subsidiaries	20,424	19,031	102,410	79,396
Equity in earnings of nonconsolidated subsidiaries	36,065	37,700	121,211	89,640
Net earnings	56,489	56,731	223,621	169,036
Net earnings attributable to Valmont Industries, Inc.	56,489	56,731	223,621	169,036
Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	161,432	160,318	501,308	441,189
Cost of sales	121,870	127,116	377,158	352,416
Gross profit	39,562	33,202	124,150	88,773
Selling, general and administrative expenses	14,530	13,449	42,871	40,414
Operating income	25,032	19,753	81,279	48,359
Other income (expense):
Interest expense	(11,122)	(12,635)	(35,696)	(37,136)
Interest income	242	398	732	721
Other	9	15	55	40
Total other income (expenses)	(10,871)	(12,222)	(34,909)	(36,375)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	14,161	7,531	46,370	11,984
Income tax expense (benefit):
Current	7,419	4,786	20,801	10,082
Deferred	(360)	(558)	1,342	(419)
Total income tax expense (benefit)	7,059	4,228	22,143	9,663
Earnings before equity in earnings of nonconsolidated subsidiaries	7,102	3,303	24,227	2,321
Equity in earnings of nonconsolidated subsidiaries	6,542	18,557	48,927	64,918
Net earnings	13,644	21,860	73,154	67,239
Net earnings attributable to Valmont Industries, Inc.	13,644	21,860	73,154	67,239
Non-Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	366,522	350,837	1,052,733	977,950
Cost of sales	273,317	266,532	795,182	757,829
Gross profit	93,205	84,305	257,551	220,121
Selling, general and administrative expenses	49,512	46,824	149,810	138,364
Operating income	43,693	37,481	107,741	81,757
Other income (expense):
Interest expense	(425)	(213)	(1,249)	(186)
Interest income	12,422	14,314	39,696	42,466
Other	(2,015)	409	(2,184)	(1,021)
Total other income (expenses)	9,982	14,510	36,263	41,259
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	53,675	51,991	144,004	123,016
Income tax expense (benefit):
Current	13,631	15,701	40,283	36,871
Deferred	8,783	2,140	4,856	314
Total income tax expense (benefit)	22,414	17,841	45,139	37,185
Earnings before equity in earnings of nonconsolidated subsidiaries	31,261	34,150	98,865	85,831
Equity in earnings of nonconsolidated subsidiaries		918	207	4,850
Net earnings	31,261	35,068	99,072	90,681
Less: Earnings attributable to noncontrolling interests	(2,402)	(1,711)	(4,726)	(3,153)
Net earnings attributable to Valmont Industries, Inc.	28,859	33,357	94,346	87,528
Eliminations
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	(81,447)	(82,983)	(252,675)	(218,785)
Cost of sales	(81,411)	(82,750)	(255,744)	(217,460)
Gross profit	(36)	(233)	3,069	(1,325)
Operating income	(36)	(233)	3,069	(1,325)
Other income (expense):
Interest expense	11,122	12,634	35,696	37,135
Interest income	(11,122)	(12,634)	(35,696)	(37,135)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	(36)	(233)	3,069	(1,325)
Income tax expense (benefit):
Current	(65)	(655)	772	(655)
Total income tax expense (benefit)	(65)	(655)	772	(655)
Earnings before equity in earnings of nonconsolidated subsidiaries	29	422	2,297	(670)
Equity in earnings of nonconsolidated subsidiaries	(42,532)	(55,639)	(169,797)	(154,097)
Net earnings	(42,503)	(55,217)	(167,500)	(154,767)
Net earnings attributable to Valmont Industries, Inc.	$ (42,503)	$ (55,217)	$ (167,500)	$ (154,767)