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Foster Company Net Income (Loss) Attributable to Parent Payment period Litigation Settlement Installment Payment Term Litigation Settlement Installment Payment Term Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Leases Lessee, Finance Leases [Text Block] Performance Based PerformanceBasedMember Remainder of 2022 Finance Lease, Liability, to be Paid, Remainder of Fiscal Year Subsequent Event Type [Axis] Subsequent Event Type [Axis] Amortization of prior service costs and transition amount Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Operating Leases Lessee, Operating Lease, Liability, to be Paid [Abstract] Accounts Receivable Additional Disclosures [Abstract] Equity Component [Domain] Equity Component [Domain] Net cash used in discontinued operating activities Cash Provided by (Used in) Operating Activities, Discontinued Operations Subsequent Event Type [Domain] Subsequent Event Type [Domain] Total assets Assets, Fair Value Disclosure Leases Lessee, Operating Leases [Text Block] Amortization of finance leases Finance Lease, Right-of-Use Asset, Amortization Total Debt and Lease Obligation Operating leases Operating Lease, Assets And Liabilities, Lessee [Abstract] Operating Lease, Assets And Liabilities, Lessee Lessee, Lease, Description Lessee, Lease, Description [Line Items] Treasury stock - at cost, 384,829 and 445,436 common stock shares at June 30, 2022 and December 31, 2021, respectively Treasury Stock, Common, Value Contract assets - net Contract with Customer, Asset, after Allowance for Credit Loss PNC Bank N.A. Citizens Bank N.A. Wells Fargo Bank National Association Bank of America N.A. And BMO Harris Bank National Association PNC Bank N.A. Citizens Bank N.A. Wells Fargo Bank National Association Bank of America N.A. And BMO Harris Bank National Association [Member] PNC Bank N.A. Citizens Bank N.A. Wells Fargo Bank National Association Bank of America N.A. 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Provided by (Used in) Investing Activities [Abstract] Weighted average shares outstanding (in shares) Weighted Average Number of Shares Issued, Basic Issuance of common shares, net of share withheld for taxes Stock Issued During Period, Value, New Issues Technology Technology-Based Intangible Assets [Member] Litigation settlement amount, non-current Litigation Settlement, Amount Awarded to Other Party, Non-Current Litigation Settlement, Amount Awarded to Other Party, Non-Current Entity Common Stock, Shares Outstanding (in shares) Entity Common Stock, Shares Outstanding Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Revolving credit facility Revolving Credit Facility [Member] Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Anticipated clean period Remedial Work Anticipated Clean Up Period Remedial Work Anticipated Clean Up Period Document Type Document Type Point in time Transferred at Point in Time [Member] 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Shell Company Entity Shell Company Deferred income taxes Deferred Income Tax Expense (Benefit) 2023 Lessee, Operating Lease, Liability, to be Paid, Year One Subsequent Event Subsequent Event [Member] Consolidation Items [Domain] Consolidation Items [Domain] Document Period End Date Document Period End Date Vesting period one Share-Based Payment Arrangement, Tranche One [Member] Schedule of Costs of Retirement Plans Schedule of Costs of Retirement Plans [Table Text Block] TOTAL ASSETS Assets Assets Write-off against allowance Accounts Receivable, Allowance for Credit Loss, Writeoff Debt Disclosure [Abstract] Earnings Per Share [Abstract] Income Statement Location [Axis] Income Statement Location [Axis] Defined benefit plan, contributions by employer Defined Benefit Plan, Plan Assets, Contributions by Employer Performance Share Units Performance Shares [Member] Other accrued liabilities Accrued Liabilities, Current Net cash provided by (used in) continuing financing activities Net Cash 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[Member] Entity Address, City Entity Address, City or Town Retirement Plans Retirement Benefits [Text Block] Leases [Abstract] Leases [Abstract] Total stockholders’ equity Beginning balance Ending balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Minimum interest coverage ratio Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Debt Instrument, Covenant, Interest Coverage Ratio, Minimum Minimum Minimum [Member] Noncontrolling interest Stockholders' Equity Attributable to Noncontrolling Interest Statement of Financial Position [Abstract] Entity Emerging Growth Company Entity Emerging Growth Company Common stock, par value (usd per share) Common Stock, Par or Stated Value Per Share Unrealized gain on cash flow hedges, net of tax expense of $50, $0, $238,and $0, respectively Unrealized derivative gain on cash flow hedges Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, after Tax Commitments and 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Foster Company stockholders’ equity Stockholders' Equity Attributable to Parent Director Director [Member] Weighted average grant date fair value, cancelled and forfeited (usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Vesting [Domain] Vesting [Domain] Line of Credit Facility Line of Credit Facility [Line Items] Entity Interactive Data Current Entity Interactive Data Current Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Skratch Enterprises Ltd Skratch Enterprises Ltd [Member] Skratch Enterprises Ltd Member Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Change in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Numerator for basic and diluted loss per common share: Net Income (Loss) Attributable to Parent [Abstract] 2025 Finite-Lived Intangible Asset, Expected Amortization, Year Three Retained Earnings Retained Earnings [Member] Segment Reporting Information Segment Reporting Information Segment Reporting Information [Line Items] Deferred Stock Units Deferred Stock Units [Member] Deferred Stock Units Total lease cost Lease, Cost Common Stock Common Stock [Member] Components of Lease Cost Lease, Cost [Table Text Block] Number of reportable segments Number of Reportable Segments Treasury stock acquisitions Payments for Repurchase of Common Stock Statement [Table] Statement [Table] Repayments of debt Repayments of Other Long-Term Debt Retirement Plan Sponsor Location [Axis] Retirement Plan Sponsor Location [Axis] Vested (usd per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Document Quarterly Report Document Quarterly Report Current assets: Assets, Current [Abstract] Accrued settlement Increase (Decrease) in Accrued Settlement Increase (Decrease) in Accrued Settlement Long-term operating lease liabilities Long-term operating lease liabilities Operating Lease, Liability, Noncurrent 2027 and thereafter Lessee, Operating Lease Liability Payments, Due After Year Four Lessee, Operating Lease Liability Payments, Due After Year Four Pension liability adjustment Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Expenses associated with contributions made Defined Contribution Plan, Cost Range [Axis] Statistical Measurement [Axis] Technology Services and Solutions Rail Technologies Products [Member] Rail Technologies Products Foreign currency translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Noncontrolling Interest Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Retained earnings Retained Earnings (Accumulated Deficit) Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Revenue Recognition Basis [Domain] Revenue Recognition Basis [Domain] [Domain] for Revenue Recognition Basis [Axis] Prior Credit Facility Prior Credit Facility [Member] Prior Credit Facility Equity Components [Axis] Equity Components [Axis] Investment of noncontrolling interest Proceeds from Noncontrolling Interests Timing of Transfer of Good or Service [Axis] Timing of Transfer of Good or Service [Axis] Document Fiscal Year Focus Document Fiscal Year Focus Foreign Plan Foreign Plan [Member] United Kingdom UNITED KINGDOM CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Statement Statement [Line Items] Financing cash flows related to finance leases Finance Lease, Principal Payments Proceeds from debt Proceeds from Issuance of Other Long-Term Debt Outstanding, Beginning balance (in shares) Outstanding, Ending balance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Variable Rate [Domain] Variable Rate [Domain] Fair Value, Hierarchy [Axis] Fair Value Hierarchy and NAV [Axis] Intangible assets Gross Carrying Value Finite-Lived Intangible Assets, Gross Selling and administrative expenses Selling, General and Administrative Expense Sales of goods Product [Member] Operating lease right-of-use assets - net Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Accumulated Other Comprehensive Loss AOCI Attributable to Parent [Member] Finance lease, liability, current, statement of financial position Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration] Document Transition Report Document Transition Report Local Phone Number Local Phone Number Operating profit Operating profit Operating profit for reportable segments Operating Income (Loss) Inventories Increase (Decrease) in Inventories Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Line of credit facility, current borrowing capacity Line of Credit Facility, Current Borrowing Capacity Effect of dilutive securities: Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Sales of services Service [Member] Goodwill Goodwill, beginning balance Goodwill, ending balance Goodwill Warranty Liability Movement in Standard Product Warranty Accrual [Roll Forward] Balance Sheet Locations Lessee, Balance Sheet Locations [Table Text Block] Lessee, Balance Sheet Locations Property, Plant and Equipment, Type [Axis] Long-Lived Tangible Asset [Axis] Adjustments to reconcile net income to cash (used in) provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Goodwill and Other Intangible Assets Goodwill and Intangible Assets Disclosure [Text Block] Beginning balance Ending balance Standard Product Warranty Accrual Income tax expense Income Tax Expense (Benefit) Product Liability Contingency [Table] Product Liability Contingency [Table] Finance lease, right-of-use asset, statement of financial position Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] Defined contribution plan number DefinedContributionPlanNumber Deferred tax liabilities Deferred Income Tax Liabilities, Net Schedule of Product Warranty Liability Schedule of Product Warranty Liability [Table Text Block] 2026 Lessee, Operating Lease, Liability, to be Paid, Year Four Income Statement [Abstract] 2023 Litigation Settlement, Amount Awarded to Other Party, Scheduled Payment Year One Litigation Settlement, Amount Awarded to Other Party, Scheduled Payment Year One Fourth Amended And Restated Credit Agreement Fourth Amended And Restated Credit Agreement [Member] Fourth Amended And Restated Credit Agreement Paid-in Capital Additional Paid-in Capital [Member] Document Fiscal Period Focus Document Fiscal Period Focus Proceeds from asset divestiture Proceeds from Sale of Equity Method Investments Denominator for diluted income (loss) per common share - 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Foster Company Comprehensive Income (Loss), Net of Tax, Attributable to Parent Rail, Technologies, and Services Rail Technologies and Services Segment [Member] Rail Technologies and Services Segment Skratch acquisition Goodwill, Acquired During Period Net cash (used in) provided by continuing operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Impairments of property, plant, and equipment Impairment of Long-Lived Assets to be Disposed of Construction in progress Construction in Progress [Member] Entity Current Reporting Status Entity Current Reporting Status Fabricated Steel Products Fabricated Steel Products [Member] Fabricated Steel Products Goodwill and Intangible Assets Disclosure [Abstract] Other assets Other Assets, Noncurrent Accrued payroll and employee benefits Increase (Decrease) in Employee Related Liabilities 2023 Finance Lease, Liability, to be Paid, Year One Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Swap Swap [Member] Revenue Recognition Basis [Axis] Revenue Recognition Basis [Axis] Revenue Recognition Basis Additions to warranty liability Standard Product Warranty Accrual, Increase for Warranties Issued Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code 2024 Finance Lease, Liability, to be Paid, Year Two Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Operating cash flows related to operating leases Operating Lease, Payments Estimated Future Amortization Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Other noncurrent assets Increase (Decrease) in Other Noncurrent Assets Domestic Plan Domestic Plan [Member] Title of Individual [Domain] Title of Individual [Domain] Debt Instrument, Redemption, Period [Domain] Debt Instrument, Redemption, Period [Domain] Finance lease, liability, noncurrent, statement of financial position Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible Enumeration] Cancelled and forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Other (income) expense - 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