GUARANTOR/NON-GUARANTOR FINANCIAL INFORMATION (Details 5) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013	Mar. 30, 2013	Dec. 29, 2012
Current assets:
Cash and cash equivalents	$ 488,195	$ 613,706	$ 419,996	$ 414,129
Receivables, net	529,693	515,440
Inventories	424,825	380,000
Prepaid expenses	57,913	22,997
Refundable and deferred income taxes	57,935	65,697
Total current assets	1,558,561	1,597,840
Property, plant and equipment, at cost	1,171,914	1,017,126
Less accumulated depreciation and amortization	559,711	482,916
Net property, plant and equipment	612,203	534,210
Goodwill	355,844	349,632
Other intangible assets	226,469	170,917
Other assets	132,789	123,895
Total assets	2,885,866	2,776,494
Current liabilities:
Current installments of long-term debt	188	202
Notes payable to banks	14,860	19,024
Accounts payable	234,218	216,121
Accrued employee compensation and benefits	86,327	122,967
Accrued expenses	91,110	71,560
Income taxes payable	9,967
Dividends payable	6,721	6,706
Total current liabilities	443,391	436,580
Deferred income taxes	104,642	78,924
Long-term debt, excluding current installments	479,141	470,907
Defined benefit pension liability	139,047	154,397
Deferred compensation	46,502	39,109
Other noncurrent liabilities	53,340	51,731
Shareholders' equity:
Common stock of $1 par value	27,900	27,900
Retained earnings	1,615,696	1,562,670
Accumulated other comprehensive income (loss)	(35,510)	(47,685)
Treasury stock	(19,897)	(20,860)
Total Valmont Industries, Inc. shareholders' equity	1,588,189	1,522,025
Noncontrolling interest in consolidated subsidiaries	31,614	22,821
Total shareholders' equity	1,619,803	1,544,846	1,463,925	1,407,010
Total liabilities and shareholders' equity	2,885,866	2,776,494
Parent
Current assets:
Cash and cash equivalents	81,941	215,576	85,432	40,926
Receivables, net	153,129	139,179
Inventories	153,676	132,953
Prepaid expenses	4,449	4,735
Refundable and deferred income taxes	34,436	41,167
Total current assets	427,631	533,610
Property, plant and equipment, at cost	533,430	522,734
Less accumulated depreciation and amortization	305,571	300,066
Net property, plant and equipment	227,859	222,668
Goodwill	20,108	20,108
Other intangible assets	333	346
Investment in subsidiaries and intercompany accounts	1,579,856	1,417,425
Other assets	38,829	30,759
Total assets	2,294,616	2,224,916
Current liabilities:
Current installments of long-term debt	188	188
Accounts payable	71,447	62,153
Accrued employee compensation and benefits	42,853	76,370
Accrued expenses	37,997	28,362
Income taxes payable	9,561
Dividends payable	6,721	6,706
Total current liabilities	168,767	173,779
Deferred income taxes	18,763	18,983
Long-term debt, excluding current installments	469,796	470,175
Deferred compensation	39,420	32,339
Other noncurrent liabilities	9,681	7,615
Shareholders' equity:
Common stock of $1 par value	27,900	27,900
Retained earnings	1,615,696	1,562,670
Accumulated other comprehensive income (loss)	(35,510)	(47,685)
Treasury stock	(19,897)	(20,860)
Total Valmont Industries, Inc. shareholders' equity	1,588,189	1,522,025
Total shareholders' equity	1,588,189	1,522,025
Total liabilities and shareholders' equity	2,294,616	2,224,916
Guarantors
Current assets:
Cash and cash equivalents	29,825	49,053	34,501	83,203
Receivables, net	84,621	108,646
Inventories	67,478	70,231
Prepaid expenses	843	932
Refundable and deferred income taxes	8,558	8,351
Total current assets	191,325	237,213
Property, plant and equipment, at cost	127,203	125,764
Less accumulated depreciation and amortization	63,265	61,520
Net property, plant and equipment	63,938	64,244
Goodwill	107,542	107,542
Other intangible assets	47,257	48,461
Investment in subsidiaries and intercompany accounts	1,419,723	1,367,308
Total assets	1,829,785	1,824,768
Current liabilities:
Accounts payable	19,188	20,365
Accrued employee compensation and benefits	5,157	13,713
Accrued expenses	5,928	7,315
Income taxes payable	(9)
Total current liabilities	30,264	41,393
Deferred income taxes	29,074	29,279
Long-term debt, excluding current installments	535,270	514,223
Shareholders' equity:
Common stock of $1 par value	457,950	457,950
Additional paid-in capital	150,286	150,286
Retained earnings	580,858	565,193
Accumulated other comprehensive income (loss)	46,083	66,444
Total Valmont Industries, Inc. shareholders' equity	1,235,177	1,239,873
Total shareholders' equity	1,235,177	1,239,873
Total liabilities and shareholders' equity	1,829,785	1,824,768
Non-Guarantors
Current assets:
Cash and cash equivalents	376,429	349,077	300,063	290,000
Receivables, net	291,943	267,615
Inventories	203,671	176,816
Prepaid expenses	52,621	17,330
Refundable and deferred income taxes	14,941	16,179
Total current assets	939,605	827,017
Property, plant and equipment, at cost	511,281	368,628
Less accumulated depreciation and amortization	190,875	121,330
Net property, plant and equipment	320,406	247,298
Goodwill	228,194	221,982
Other intangible assets	178,879	122,110
Investment in subsidiaries and intercompany accounts	494,656	518,059
Other assets	93,960	93,136
Total assets	2,255,700	2,029,602
Current liabilities:
Current installments of long-term debt		14
Notes payable to banks	14,860	19,024
Accounts payable	143,583	133,603
Accrued employee compensation and benefits	38,317	32,884
Accrued expenses	47,185	35,883
Income taxes payable	415
Total current liabilities	244,360	221,408
Deferred income taxes	56,805	30,662
Long-term debt, excluding current installments	9,345	732
Defined benefit pension liability	139,047	154,397
Deferred compensation	7,082	6,770
Other noncurrent liabilities	43,659	44,116
Shareholders' equity:
Common stock of $1 par value	254,982	254,982
Additional paid-in capital	1,034,236	891,236
Retained earnings	535,220	517,703
Accumulated other comprehensive income (loss)	(100,650)	(115,225)
Total Valmont Industries, Inc. shareholders' equity	1,723,788	1,548,696
Noncontrolling interest in consolidated subsidiaries	31,614	22,821
Total shareholders' equity	1,755,402	1,571,517
Total liabilities and shareholders' equity	2,255,700	2,029,602
Eliminations
Current assets:
Investment in subsidiaries and intercompany accounts	(3,494,235)	(3,302,792)
Total assets	(3,494,235)	(3,302,792)
Current liabilities:
Long-term debt, excluding current installments	(535,270)	(514,223)
Shareholders' equity:
Common stock of $1 par value	(712,932)	(712,932)
Additional paid-in capital	(1,184,522)	(1,041,522)
Retained earnings	(1,116,078)	(1,082,896)
Accumulated other comprehensive income (loss)	54,567	48,781
Total Valmont Industries, Inc. shareholders' equity	(2,958,965)	(2,788,569)
Total shareholders' equity	(2,958,965)	(2,788,569)
Total liabilities and shareholders' equity	$ (3,494,235)	$ (3,302,792)