GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Condensed consolidated financial information for the Company (Parent), the Guarantor subsidiaries and the Non-Guarantor subsidiaries
Net sales	$ 842,599	$ 878,659	$ 1,594,339	$ 1,698,289
Cost of sales	622,122	617,188	1,166,880	1,201,449
Gross profit	220,477	261,471	427,459	496,840
Selling, general and administrative expenses	115,701	117,206	223,835	234,385
Operating income	104,776	144,265	203,624	262,455
Other income (expense):
Interest expense	(8,304)	(8,025)	(16,501)	(16,215)
Interest income	1,577	1,852	3,316	3,205
Other	1,903	123	(3,909)	1,679
Total other income (expenses)	(4,824)	(6,050)	(17,094)	(11,331)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	99,952	138,215	186,530	251,124
Income tax expense (benefit):
Current	26,117	48,210	59,055	86,870
Deferred	7,953	(1,042)	5,030	(4,729)
Total income tax expense (benefit)	34,070	47,168	64,085	82,141
Earnings before equity in earnings of nonconsolidated subsidiaries	65,882	91,047	122,445	168,983
Equity in earnings of nonconsolidated subsidiaries	(30)	269	(30)	473
Net earnings	65,852	91,316	122,415	169,456
Less: Earnings attributable to noncontrolling interests	(1,876)	(1,753)	(2,459)	(2,324)
Net earnings attributable to Valmont Industries, Inc.	63,976	89,563	119,956	167,132
Parent
Condensed consolidated financial information for the Company (Parent), the Guarantor subsidiaries and the Non-Guarantor subsidiaries
Net sales	378,642	426,817	755,284	843,430
Cost of sales	280,054	297,949	551,813	598,629
Gross profit	98,588	128,868	203,471	244,801
Selling, general and administrative expenses	50,164	55,720	97,954	105,746
Operating income	48,424	73,148	105,517	139,055
Other income (expense):
Interest expense	(7,691)	(7,636)	(15,366)	(15,391)
Interest income	6	8	26	15
Other	1,754	394	1,821	1,802
Total other income (expenses)	(5,931)	(7,234)	(13,519)	(13,574)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	42,493	65,914	91,998	125,481
Income tax expense (benefit):
Current	9,315	24,824	29,193	45,999
Deferred	7,672	(750)	5,829	(2,504)
Total income tax expense (benefit)	16,987	24,074	35,022	43,495
Earnings before equity in earnings of nonconsolidated subsidiaries	25,506	41,840	56,976	81,986
Equity in earnings of nonconsolidated subsidiaries	38,470	47,723	62,980	85,146
Net earnings	63,976	89,563	119,956	167,132
Net earnings attributable to Valmont Industries, Inc.	63,976	89,563	119,956	167,132
Guarantors
Condensed consolidated financial information for the Company (Parent), the Guarantor subsidiaries and the Non-Guarantor subsidiaries
Net sales	124,414	169,027	260,311	339,876
Cost of sales	91,536	126,290	191,352	255,288
Gross profit	32,878	42,737	68,959	84,588
Selling, general and administrative expenses	12,670	14,347	25,661	28,341
Operating income	20,208	28,390	43,298	56,247
Other income (expense):
Interest expense	(11,337)	(11,944)	(22,217)	(24,574)
Interest income	152	237	335	490
Other	140	31	(352)	46
Total other income (expenses)	(11,045)	(11,676)	(22,234)	(24,038)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	9,163	16,714	21,064	32,209
Income tax expense (benefit):
Current	2,626	6,546	8,213	13,382
Deferred	2,079	1,399	1,667	1,702
Total income tax expense (benefit)	4,705	7,945	9,880	15,084
Earnings before equity in earnings of nonconsolidated subsidiaries	4,458	8,769	11,184	17,125
Equity in earnings of nonconsolidated subsidiaries	16,964	23,234	25,903	42,385
Net earnings	21,422	32,003	37,087	59,510
Net earnings attributable to Valmont Industries, Inc.	21,422	32,003	37,087	59,510
Non-Guarantors
Condensed consolidated financial information for the Company (Parent), the Guarantor subsidiaries and the Non-Guarantor subsidiaries
Net sales	387,715	360,802	687,996	686,211
Cost of sales	298,764	273,482	533,398	521,865
Gross profit	88,951	87,320	154,598	164,346
Selling, general and administrative expenses	52,867	47,139	100,220	100,298
Operating income	36,084	40,181	54,378	64,048
Other income (expense):
Interest expense	(613)	(390)	(1,135)	(824)
Interest income	12,756	13,552	25,172	27,274
Other	9	(302)	(5,378)	(169)
Total other income (expenses)	12,152	12,860	18,659	26,281
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	48,236	53,041	73,037	90,329
Income tax expense (benefit):
Current	14,148	16,182	21,517	26,652
Deferred	(1,798)	(1,691)	(2,466)	(3,927)
Total income tax expense (benefit)	12,350	14,491	19,051	22,725
Earnings before equity in earnings of nonconsolidated subsidiaries	35,886	38,550	53,986	67,604
Equity in earnings of nonconsolidated subsidiaries				207
Net earnings	35,886	38,550	53,986	67,811
Less: Earnings attributable to noncontrolling interests	(1,876)	(1,753)	(2,459)	(2,324)
Net earnings attributable to Valmont Industries, Inc.	34,010	36,797	51,527	65,487
Eliminations
Condensed consolidated financial information for the Company (Parent), the Guarantor subsidiaries and the Non-Guarantor subsidiaries
Net sales	(48,172)	(77,987)	(109,252)	(171,228)
Cost of sales	(48,232)	(80,533)	(109,683)	(174,333)
Gross profit	60	2,546	431	3,105
Operating income	60	2,546	431	3,105
Other income (expense):
Interest expense	11,337	11,945	22,217	24,574
Interest income	(11,337)	(11,945)	(22,217)	(24,574)
Earnings before income taxes and equity in earnings of nonconsolidated subsidiaries	60	2,546	431	3,105
Income tax expense (benefit):
Current	28	658	132	837
Total income tax expense (benefit)	28	658	132	837
Earnings before equity in earnings of nonconsolidated subsidiaries	32	1,888	299	2,268
Equity in earnings of nonconsolidated subsidiaries	(55,464)	(70,688)	(88,913)	(127,265)
Net earnings	(55,432)	(68,800)	(88,614)	(124,997)
Net earnings attributable to Valmont Industries, Inc.	$ (55,432)	$ (68,800)	$ (88,614)	$ (124,997)