Document And Entity Information Document Type Document Type Document Annual Report Document Annual Report Document Period End Date Document Period End Date Current Fiscal Year End Date Current Fiscal Year End Date Document Transition Report Document Transition Report Securities Act File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Smaller Reporting Company Entity Emerging Growth Company Emerging Growth Company ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Document Financial Statement Error Correction [Flag] Entity Shell Company Shell Company Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Documents Incorporated by Reference [Text Block] Documents Incorporated by Reference Entity Central Index Key Entity Central Index Key Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Auditor Name Auditor Location Auditor Firm ID CONSOLIDATED STATEMENTS OF EARNINGS Statement [Table] Statement [Table] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] Product [Member] Product sales Service [Member] Service sales Statement [Line Items] Statement Revenue from Contract with Customer, Excluding Assessed Tax Net sales Total net sales Cost of Goods and Services Sold Cost of sales Total cost of sales Gross Profit Gross profit Selling, General and Administrative Expense Selling, general, and administrative expenses Asset Impairment Charges Impairment of long-lived assets Restructuring Charges Realignment charges Restructuring charges Operating Income (Loss) Total operating income Operating income Nonoperating Income (Expense) [Abstract] Other income (expenses): Interest Expense, Nonoperating Interest expense Investment Income, Interest Interest income Debt and Equity Securities, Unrealized Gain (Loss) Gain on deferred compensation investments Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal Loss (gain) on divestitures Pre-tax gain (loss) on sale of engineering and equipment Gain (loss) on divestitures Other Nonoperating Income (Expense) Other Nonoperating Income (Expense) Total other expenses Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Earnings before income taxes and equity method investment loss Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Income tax expense (benefit): Current Income Tax Expense (Benefit) Current Deferred Income Tax Expense (Benefit) Deferred Total deferred income tax benefit Deferred income taxes Income Tax Expense (Benefit) Total income tax expense Total income tax expense Income (Loss) from Continuing Operations before Equity Method Investments and Noncontrolling Interest Income (Loss) from Continuing Operations before Equity Method Investments and Noncontrolling Interest Earnings before equity method investment loss Income (Loss) from Equity Method Investments Equity method investment loss Equity method investment loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net earnings Net earnings Net earnings Net Income (Loss) Attributable to Redeemable Noncontrolling Interest Loss (earnings) attributable to redeemable noncontrolling interests Net earnings attributable to Valmont Industries, Inc. Net earnings (loss) NET EARNINGS PER SHARE Net earnings attributable to Valmont Industries, Inc. per share: Earnings Per Share, Basic Basic Basic (in dollars per share) Earnings Per Share, Diluted Diluted Diluted (in dollars per share) Diluted loss per share, correction CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax [Abstract] Foreign currency translation adjustments: Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax Unrealized translation gain (loss) Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax [Abstract] Hedging activities: Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, after Tax Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), Reclassification, after Tax Unrealized gain (loss) on commodity hedges Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), After Reclassification and Tax Other Comprehensive Income (Loss), Net Investment Hedge, Gain (Loss), After Reclassification and Tax Realized loss (gain) on commodity hedges included in net earnings Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net Unrealized gain (loss) on cross currency swaps Other Comprehensive Income (Loss) Amortization Cost (Benefit) Included in Interest Expense Other Comprehensive Income (Loss) Amortization Cost (Benefit) Included in Interest Expense Amortization cost included in interest expense Other Comprehensive Income Loss, Hedging Activities, Gain (loss), after Reclassification and Tax Other Comprehensive Income Loss, Hedging Activities, Gain (loss), after Reclassification and Tax Total hedging activities Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Net gain (loss) on defined benefit pension plan Other Comprehensive Income (Loss), Net of Tax Total other comprehensive income (loss), net of tax Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive loss (income) attributable to redeemable noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Parent Comprehensive income attributable to Valmont Industries, Inc. CONSOLIDATED BALANCE SHEETS Assets [Abstract] ASSETS Assets, Current [Abstract] Current assets: Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Accounts Receivable, after Allowance for Credit Loss, Current Receivables, less allowance of $54,991 and $30,408, respectively Inventory, Net Inventories Contract with Customer, Asset, after Allowance for Credit Loss, Current Contract assets Income Taxes Receivable, Current Income taxes receivable Prepaid Expense and Other Assets, Current Prepaid expenses and other current assets Assets, Current Total current assets Property, Plant and Equipment, Gross Property, plant, and equipment, at cost Total property, plant, and equipment, at cost Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Less accumulated depreciation Property, Plant and Equipment, Net Property, plant, and equipment, net Goodwill Balance at the end of the period Balance at the beginning of the period Goodwill Intangible Assets, Net (Excluding Goodwill) Other intangible assets, net Assets for Plan Benefits, Defined Benefit Plan Defined benefit pension asset Operating Lease, Right-of-Use Asset Operating lease right-of-use assets Operating lease ROU assets Deferred compensation investments Assets related to non-qualified deferred compensation plan included in other assets Deferred Income Tax Assets, Net Non-current deferred tax asset Other Assets, Noncurrent Other non-current assets Assets Total assets Total assets Liabilities and Equity [Abstract] LIABILITIES, REDEEMABLE NONCONTROLLING INTERESTS, AND SHAREHOLDERS' EQUITY Liabilities, Current [Abstract] Current liabilities: Long-Term Debt, Current Maturities Current installments of long-term debt Less: Current installments of long-term debt Short-Term Bank Loans and Notes Payable Notes payable to banks Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Share Value, Amount, Current Mandatorily redeemable financial instrument Accounts Payable, Current Accounts payable Employee-related Liabilities, Current Accrued employee compensation and benefits Contract with Customer, Liability, Current Contract liabilities Accrued Liabilities, Current Other accrued expenses Taxes Payable, Current Income taxes payable Dividends Payable, Current Dividends payable Liabilities, Current Total current liabilities Deferred Income Tax Liabilities, Net Deferred income taxes Long-Term Debt, Excluding Current Maturities Long-term debt, excluding current installments Operating Lease, Liability, Noncurrent Long-term operating lease liabilities Operating lease liabilities Deferred Compensation Liability, Classified, Noncurrent Deferred compensation liabilities Other Liabilities, Noncurrent Other non-current liabilities Liabilities Total liabilities Redeemable Noncontrolling Interest, Equity, Carrying Amount Redeemable noncontrolling interests - Ending balance Redeemable noncontrolling interests - Beginning balance Redeemable noncontrolling interests Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Shareholders' equity: Common Stock, Value, Issued Common stock of $1 par value, authorized 75,000,000 shares; issued 27,900,000 shares Retained Earnings (Accumulated Deficit) Retained earnings Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive loss Accumulated other comprehensive loss Treasury Stock, Common, Value Treasury stock Equity, Attributable to Parent Total shareholders' equity - Ending balance Total shareholders' equity - Beginning balance Total shareholders' equity Liabilities and Equity Total liabilities, redeemable noncontrolling interests, and shareholders' equity Accounts Receivable, Allowance for Credit Loss, Current Receivables allowance Common Stock, Par or Stated Value Per Share Common stock, par value (in dollars per share) Common Stock, Shares Authorized Common stock, authorized shares (in shares) Common Stock, Shares, Issued Common stock, issued shares (in shares) CONSOLIDATED STATEMENTS OF CASH FLOWS Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net earnings to net cash flows from operating activities: Depreciation, Depletion and Amortization Depreciation and amortization Total depreciation and amortization expense Payment for Pension Benefits Contribution to defined benefit pension plan Share-Based Payment Arrangement, Noncash Expense Stock-based compensation Pension Expense (Reversal of Expense), Noncash Net periodic pension cost Gain (Loss) on Disposition of Property Plant Equipment Loss (gain) on sale of property, plant, and equipment Other Noncash Income (Expense) Other, net Increase (Decrease) in Operating Capital [Abstract] Changes in assets and liabilities: Increase (Decrease) in Receivables Receivables Increase (Decrease) in Inventories Inventories Increase (Decrease) in Contract with Customer, Asset Contract assets Increase (Decrease) in Prepaid Expense Prepaid expenses and other assets (current and non-current) Increase (Decrease) in Accounts Payable Accounts payable Increase (Decrease) in Contract with Customer, Liability Contract liabilities (current and non-current) Increase (Decrease) in Accrued Liabilities Accrued expenses Increase (Decrease) in Income Taxes Payable Current income taxes Increase (Decrease) in Other Operating Liabilities Other non-current liabilities Net Cash Provided by (Used in) Operating Activities Net cash flows from operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities: Payments to Acquire Property, Plant, and Equipment Purchases of property, plant, and equipment Proceeds from Divestiture of Businesses, Net of Cash Divested Proceeds from divestitures, net of cash divested Proceeds from Sale of Productive Assets Proceeds from sales of assets Proceeds from Insurance Settlement, Investing Activities Proceeds from property damage insurance claims Payments to Acquire Businesses, Net of Cash Acquired Acquisitions, net of cash acquired Acquisitions, net of cash acquired Payments for (Proceeds from) Other Investing Activities Other, net Net Cash Provided by (Used in) Investing Activities Net cash flows from investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities: Proceeds from Short-Term Debt Proceeds from short-term borrowings Repayments of Short-Term Debt Repayments on short-term borrowings Proceeds from Issuance of Long-Term Debt Proceeds from long-term borrowings Repayments of Long-Term Debt Principal repayments on long-term borrowings Payments for (Proceeds from) Derivative Instrument, Financing Activities Proceeds from settlement of financial derivatives Payments of Ordinary Dividends, Common Stock Dividends paid Payments of Ordinary Dividends, Noncontrolling Interest Dividends to redeemable noncontrolling interests PaymentsToAcquireAdditionalInterestInSubsidiariesFinancingActivities PaymentsToAcquireAdditionalInterestInSubsidiariesFinancingActivities Purchases of redeemable noncontrolling interests Payments for Repurchase of Common Stock Repurchases of common stock Proceeds from Stock Plans Proceeds from exercises under stock plans Payment, Tax Withholding, Share-Based Payment Arrangement Tax withholdings on exercises under stock plans Proceeds from (Payments for) Other Financing Activities Other, net Net Cash Provided by (Used in) Financing Activities Net cash flows from financing activities Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations Effect of exchange rate changes on cash and cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Net change in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents Cash and cash equivalents-end of period Cash and cash equivalents-beginning of period Supplemental Cash Flow Information [Abstract] Supplemental disclosures of cash flow information: Interest Paid, Excluding Capitalized Interest, Operating Activities Interest paid Income Taxes Paid, Net Income taxes paid Income Taxes Paid, Net, Total CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY AND REDEEMABLE NONCONTROLLING INTERESTS Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common stock Additional Paid-in Capital [Member] Additional paid-in capital Retained Earnings [Member] Retained earnings AOCI Attributable to Parent [Member] Accumulated other comprehensive loss Treasury Stock, Common [Member] Treasury stock This element represents Redeemable noncontrolling interests. Redeemable Noncontrolling Interests [Member] Redeemable noncontrolling interests Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Shareholders' Equity