GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	$ 878,659	$ 767,315	$ 1,698,289	$ 1,484,665
Cost of sales	617,188	567,920	1,201,449	1,098,956
Gross profit	261,471	199,395	496,840	385,709
Selling, general and administrative expenses	117,206	102,043	234,385	205,539
Operating income	144,265	97,352	262,455	180,170
Other income (expense):
Interest expense	(8,025)	(7,421)	(16,215)	(15,228)
Interest income	1,852	1,910	3,205	3,988
Other	123	(1,977)	1,679	(400)
Total other income (expenses)	(6,050)	(7,488)	(11,331)	(11,640)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	138,215	89,864	251,124	168,530
Income tax expense (benefit):
Current	48,210	35,985	86,870	63,014
Deferred	(1,042)	(5,193)	(4,729)	(4,456)
Total income tax expense (benefit)	47,168	30,792	82,141	58,558
Earnings before equity in earnings of nonconsolidated subsidiaries	91,047	59,072	168,983	109,972
Equity in earnings of nonconsolidated subsidiaries	269	2,087	473	3,775
Net earnings	91,316	61,159	169,456	113,747
Less: Earnings attributable to noncontrolling interests	(1,753)	(1,179)	(2,324)	(1,442)
Net earnings attributable to Valmont Industries, Inc.	89,563	59,980	167,132	112,305
Parent
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	426,817	347,643	843,430	712,483
Cost of sales	297,949	249,557	598,629	517,069
Gross profit	128,868	98,086	244,801	195,414
Selling, general and administrative expenses	55,720	43,762	105,746	87,034
Operating income	73,148	54,324	139,055	108,380
Other income (expense):
Interest expense	(7,636)	(7,573)	(15,391)	(15,255)
Interest income	8	5	15	14
Other	394	(454)	1,802	1,005
Total other income (expenses)	(7,234)	(8,022)	(13,574)	(14,236)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	65,914	46,302	125,481	94,144
Income tax expense (benefit):
Current	24,824	19,363	45,999	36,548
Deferred	(750)	(2,963)	(2,504)	(2,769)
Total income tax expense (benefit)	24,074	16,400	43,495	33,779
Earnings before equity in earnings of nonconsolidated subsidiaries	41,840	29,902	81,986	60,365
Equity in earnings of nonconsolidated subsidiaries	47,723	30,078	85,146	51,940
Net earnings	89,563	59,980	167,132	112,305
Net earnings attributable to Valmont Industries, Inc.	89,563	59,980	167,132	112,305
Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	169,027	152,159	339,876	280,871
Cost of sales	126,290	121,658	255,288	225,300
Gross profit	42,737	30,501	84,588	55,571
Selling, general and administrative expenses	14,347	13,177	28,341	26,965
Operating income	28,390	17,324	56,247	28,606
Other income (expense):
Interest expense	(11,944)	(12,244)	(24,574)	(24,501)
Interest income	237	129	490	323
Other	31	11	46	25
Total other income (expenses)	(11,676)	(12,104)	(24,038)	(24,153)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	16,714	5,220	32,209	4,453
Income tax expense (benefit):
Current	6,546	6,197	13,382	5,296
Deferred	1,399	(1,031)	1,702	139
Total income tax expense (benefit)	7,945	5,166	15,084	5,435
Earnings before equity in earnings of nonconsolidated subsidiaries	8,769	54	17,125	(982)
Equity in earnings of nonconsolidated subsidiaries	23,234	23,253	42,385	46,361
Net earnings	32,003	23,307	59,510	45,379
Net earnings attributable to Valmont Industries, Inc.	32,003	23,307	59,510	45,379
Non-Guarantors
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	360,802	333,171	686,211	627,113
Cost of sales	273,482	261,374	521,865	491,297
Gross profit	87,320	71,797	164,346	135,816
Selling, general and administrative expenses	47,139	45,104	100,298	91,540
Operating income	40,181	26,693	64,048	44,276
Other income (expense):
Interest expense	(390)	152	(824)	27
Interest income	13,552	14,020	27,274	28,152
Other	(302)	(1,534)	(169)	(1,430)
Total other income (expenses)	12,860	12,638	26,281	26,749
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	53,041	39,331	90,329	71,025
Income tax expense (benefit):
Current	16,182	10,425	26,652	21,170
Deferred	(1,691)	(1,199)	(3,927)	(1,826)
Total income tax expense (benefit)	14,491	9,226	22,725	19,344
Earnings before equity in earnings of nonconsolidated subsidiaries	38,550	30,105	67,604	51,681
Equity in earnings of nonconsolidated subsidiaries		2,276	207	3,932
Net earnings	38,550	32,381	67,811	55,613
Less: Earnings attributable to noncontrolling interests	(1,753)	(1,179)	(2,324)	(1,442)
Net earnings attributable to Valmont Industries, Inc.	36,797	31,202	65,487	54,171
Eliminations
Condensed consolidated financial information for the Company (Parent), the guarantor subsidiaries and the non-guarantor subsidiaries
Net sales	(77,987)	(65,658)	(171,228)	(135,802)
Cost of sales	(80,533)	(64,669)	(174,333)	(134,710)
Gross profit	2,546	(989)	3,105	(1,092)
Operating income	2,546	(989)	3,105	(1,092)
Other income (expense):
Interest expense	11,945	12,244	24,574	24,501
Interest income	(11,945)	(12,244)	(24,574)	(24,501)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	2,546	(989)	3,105	(1,092)
Income tax expense (benefit):
Current	658		837
Total income tax expense (benefit)	658		837
Earnings before equity in earnings of nonconsolidated subsidiaries	1,888	(989)	2,268	(1,092)
Equity in earnings of nonconsolidated subsidiaries	(70,688)	(53,520)	(127,265)	(98,458)
Net earnings	(68,800)	(54,509)	(124,997)	(99,550)
Net earnings attributable to Valmont Industries, Inc.	$ (68,800)	$ (54,509)	$ (124,997)	$ (99,550)