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Morgan Chase Bank J.P. Morgan Chase Bank [Member] J.P. Morgan Chase Bank Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Project Unapproved Change Orders and Claims [Line Items] Power Generation Project Unapproved Change Orders and Claims [Line Items] [Line Items] for Power Generation Project Unapproved Change Orders and Claims [Table] Unapproved Change Orders On Power Generation Project [Member] Unapproved Change Orders On Power Generation Project [Member] Unapproved Change Orders On Power Generation Project [Member] Asset Backed Line of Credit Balance Limit for Fixed Charge Coverage Ratio mtrx:AssetBackedLineofCreditBalanceLimitforFixedChargeCoverageRatio mtrx:AssetBackedLineofCreditBalanceLimitforFixedChargeCoverageRatio Other Information Pertaining to Income Taxes Other Information Pertaining to Income Taxes Accounts receivable Increase (Decrease) in Accounts Receivable Purchases of property, plant and equipment on account Capital Expenditures Incurred but Not yet Paid Right-of-use asset obtained in exchange for operating lease liability Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Dilutive nonvested deferred shares Incremental Common Shares Attributable to Dilutive Effect of Nonvested Shares with Forfeitable Dividends Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Comprehensive loss Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Leasehold improvements received as lease incentive, non-cash investing activity Other Significant Noncash Transaction, Value of Consideration Received Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Entity Interactive Data Current Entity Interactive Data Current Line of Credit Facility, Remaining Borrowing Capacity Line of Credit Facility, Remaining Borrowing Capacity Basic loss per common share Basic EPS (US$ per share) Earnings Per Share, Basic Fiscal 2025 Lessee, Operating Lease, Liability, to be Paid, Year Three Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Finite-Lived Intangible Assets, Amortization Expense, after Year Five Finite-Lived Intangible Asset, Expected Amortization, after Year Five Document Type Document Type Canada CANADA Revenue from External Customers by Contract Type Disaggregation of Revenue [Table Text Block] Amount of fair value in excess of carrying amount Reporting Unit, Amount of Fair Value in Excess of Carrying Amount Earnings Per Share, Diluted [Abstract] Earnings Per Share, Diluted [Abstract] Entity Current Reporting Status Entity Current Reporting Status Construction equipment Machinery and Equipment, Gross Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net Cash paid for operating leases Operating Lease, Payments Other Other Noncash Income (Expense) Additional Margin on alternate base rate loans, Maximum Line Of Credit Basis Spread On Alternate Base Rate Maximum Line of credit basis spread on alternate base rate maximum. Provision for uncollectible accounts Accounts Receivable, Credit Loss Expense (Reversal) Goodwill [Roll Forward] Goodwill [Roll Forward] Storage and Terminal Solutions Storage and Terminal Solutions [Member] Storage and Terminal Solutions Other liabilities, non-current Liabilities, Other than Long-term Debt, Noncurrent Accrued insurance Accrued Insurance, Current Investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Goodwill impairment Goodwill, Impairment Loss Document Transition Report Document Transition Report Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Lessee, Operating Lease, Liability, Payment, Due [Abstract] Lessee, Operating Lease, Liability, Payment, Due [Abstract] Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Total liabilities and stockholders’ equity Liabilities and Equity Billings on uncompleted contracts in excess of costs and estimated earnings Billings on uncompleted contracts in excess of costs and estimated earnings Contract with Customer, Liability, Current Additional paid-in capital Additional Paid in Capital Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill) Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Accounts payable Increase (Decrease) in Accounts Payable Earnings per Common Share Earnings Per Share [Text Block] Operating lease right-of-use asset impairment Operating Lease, Impairment Loss Open market purchases of treasury shares Treasury Stock, Value, Acquired, Cost Method Finite-Lived Intangible Assets, Amortization Expense, Year Four Finite-Lived Intangible Asset, Expected Amortization, Year Four Minimum [Member] Minimum [Member] Income taxes receivable Income Taxes Receivable, Current Change in CIE Change in CIE Change in CIE from prior year to the current period. Expected effective tax rate, year-to-date Expected effective tax rate, year-to-date Expected effective tax rate year-to-date. Gross profit (loss) Gross profit (loss) Gross Profit Fiscal 2024 Lessee, Operating Lease, Liability, to be Paid, Year Two Selling, general and administrative expenses Selling, General and Administrative Expense Proceeds from asset sales Proceeds from Sale of Productive Assets Deferred tax remeasurement Deferred tax remeasurement Deferred tax remeasurement due to the enactment of the Tax Cuts and Jobs Act of 2017. The Company's domestic net deferred tax liability balance was remeasured at a lower corporate tax rate, which reduced the net deferred tax liability balance. The downward remeasurement was recorded as a benefit to income tax expense. Restructuring reserve balance Restructuring Reserve Operating lease impairment due to restructuring Operating Lease Impairments Due To Restructuring Operating Lease Impairments Due To Restructuring Stockholders' equity Stockholders' Equity before Treasury Stock Trading Symbol Trading Symbol Deferred income taxes Deferred Income Tax Assets, Net Current liabilities: Liabilities, Current [Abstract] Debt Debt Disclosure [Text Block] Common stock, shares outstanding Shares, Outstanding Proceeds from Income Tax Refunds Proceeds from Income Tax Refunds Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] Change in Accounting Principle, Accounting Standards Update, Immaterial Effect [true false] Deferred Tax Assets, Foreign Tax Credit Carryforward, After Valuation Allowance Deferred Tax Assets, Foreign Tax Credit Carryforward, After Valuation Allowance Deferred Tax Assets, Foreign Tax Credit Carryforward, After Valuation Allowance Letters of Credit Outstanding, Amount Letters of Credit Outstanding, Amount Net present value of future lease payments Operating Lease, Liability Common stock—$.01 par value; 60,000,000 shares authorized; 27,888,217 shares issued as of March 31, 2022 and June 30, 2021; 26,783,265 and 26,549,438 shares outstanding as of March 31, 2022 and June 30, 2021, respectively Common Stock, Value, Issued Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Goodwill, Acquired During Period Goodwill, Acquired During Period Commitments and contingencies Commitments and Contingencies Lessee, Operating Leases [Text Block] Lessee, Operating Leases [Text Block] Contracts Receivable, Claims and Uncertain Amounts Contracts Receivable, Claims and Uncertain Amounts Accounts receivable, allowances Accounts Receivable, Allowance for Credit Loss, Current Remainder of Fiscal 2022 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Restructuring costs incurred mtrx:UnpaidRestructuringCharges Unpaid Restructuring Charges Payment of debt amendment fees Payments of Debt Issuance Costs Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Document Period End Date Document Period End Date Dilutive stock options Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Blended income tax rate Blended income tax rate Blended income tax rate of 28.06% used by the Company for the remainder of Fiscal 2018. The use of this blended rate is stipulated by the Internal Revenue Code in connection with the Tax Cuts and Jobs Act of December 2017, which reduced the federal income tax rate from 35% to 21%. Since the Company has a June 30 fiscal year end, it must use a blend of 21% and 35% for the rest of the current fiscal year. Goodwill [Line Items] Goodwill [Line Items] Class of Stock [Axis] Class of Stock [Axis] Revenue from External Customers by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Entity Registrant Name Entity Registrant Name Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Impairment Losses, Amount Treasury stock, shares Treasury Stock, Shares Imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Contract with Customer, Asset and Liability [Abstract] Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract] Asset Backed Line of Credit Percentage Limit for Fixed Charge Coverage Ratio mtrx:AssetBackedLineofCreditPercentageLimitforFixedChargeCoverageRatio mtrx:AssetBackedLineofCreditPercentageLimitforFixedChargeCoverageRatio Investments, Owned, Federal Income Tax Note [Line Items] Investments, Owned, Federal Income Tax Note [Line Items] Amount of Foreign Tax Credit Carryforward Expiring Between Fiscal 2023 and Fiscal 2025 Amount of Foreign Tax Credit Carryforward Expiring in Fiscal 2023 Amount of Foreign Tax Credit Carryforward Expiring in Fiscal 2023 Amount of Foreign Tax Credit Carryforward Expiring in Fiscal 2021 Amount of Foreign Tax Credit Carryforward Expiring in Fiscal 2021 Amount of Foreign Tax Credit Carryforward Expiring in Fiscal 2021 Stock Options [Member] Share-based Payment Arrangement, Option [Member] Consolidation Items [Domain] Consolidation Items [Domain] Cash payments Payments for Restructuring Effect of exchange rate changes on cash, cash equivalents and restricted cash Effect of Exchange Rate on Cash and Cash Equivalents Common Stock Common Stock [Member] Interest income Investment Income, Interest Other income (expense): Other Nonoperating Income (Expense) [Abstract] Segment Information Segment Reporting Disclosure [Text Block] Operating loss Operating Income (Loss) Operating lease liabilities Operating Lease, Liability, Current Finite-Lived Intangible Assets, Amortization Expense, Year Two Finite-Lived Intangible Asset, Expected Amortization, Year Two Schedule of Cash and Cash Equivalents [Table] Schedule of Cash and Cash Equivalents [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax Stock-based compensation expense Share-based Payment Arrangement, Noncash Expense Restructuring Costs Restructuring and Related Activities Disclosure [Text Block] Additional Paid-In Capital Additional Paid-in Capital [Member] Cash and cash equivalents (Note 1) Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Other international Other international [Member] Other international [Member] Treasury Stock Treasury Stock [Member] Asset Backed Credit Facility Base Rate Add On Asset Backed Credit Facility Base Rate Add On Asset Backed Credit Facility Base Rate Add On Accrued expenses Increase (Decrease) in Accrued Liabilities Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Other Other Nonoperating Income (Expense) Capital expenditures Payments to Acquire Property, Plant, and Equipment Tax Credit Carryforward, Valuation Allowance Tax Credit Carryforward, Valuation Allowance Other Lease Information [Abstract] Other Lease Information [Abstract] Other Lease Information [Abstract] Other accrued expenses Other Liabilities, Current Change in BIE Change in BIE Change in BIE from the prior year to the current period. Maximum [Member] Maximum [Member] CARES Act NOL Carryback Benefit mtrx:MtrxCARESActNOLCarrybackBenefit mtrx:MtrxCARESActNOLCarrybackBenefit Total liabilities Liabilities Finite-Lived Intangible Assets, Amortization Expense, Next Year Finite-Lived Intangible Asset, Expected Amortization, Year One Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress Financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Additional Margin on alternate base rate loans, Minimum Line Of Credit Basis Spread On Alternate Base Rate Minimum Line of credit basis spread on alternate base rate minimum. Lessee, Operating Lease, Liability, Maturity [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Consolidation Items [Axis] Consolidation Items [Axis] Restructuring and Related Cost, Expected Cost Remaining Restructuring and Related Cost, Expected Cost Remaining Common stock, shares issued Common Stock, Shares, Issued Total Deferred Tax Assets Outstanding in Prior Quarters Total Deferred Tax Assets Generated in the Six Months Ended December 31st, 2021 [Member] Total Deferred Tax Assets Generated in the Six Months Ended December 31st, 2021 Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Other Repayments of Other Debt Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Income Tax Receivable [Domain] Income Tax Receivable [Domain] Income Tax Receivable [Domain] Operating lease liabilities Operating Lease, Liability, Noncurrent Interest expense (Note 5) Interest Expense Transportation equipment Transportation Equipment Gross Transportation Equipment Gross City Area Code City Area Code Retained earnings Retained Earnings (Accumulated Deficit) Line Of Credit Basis Spread On Adjusted LIBO and CDOR Minimum Line Of Credit Basis Spread On Adjusted LIBO and CDOR Minimum Line Of Credit Basis Spread On Adjusted LIBO and CDOR Minimum Operating lease term (up to) Lessee, Operating Lease, Term of Contract Unused Credit Facility Fee Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Construction Contractor, Receivable, Retainage, Year One Construction Contractor, Receivable, Retainage, Year One Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Employee Stock Purchase Plan, shares Stock Issued During Period, Shares, Employee Stock Purchase Plans Restrictions on Cash and Cash Equivalents Restrictions on Cash and Cash Equivalents [Table Text Block] Income Statement [Abstract] Income Statement [Abstract] Amendment Flag Amendment Flag Repurchase of common stock for payment of statutory taxes due on equity-based compensation Payments for Repurchase of Other Equity Issuances of common stock Proceeds from Stock Options Exercised Basis of Presentation Basis of Presentation and Significant Accounting Policies [Text Block] Issuance of deferred shares, shares Deferred Shares Issued Deferred Shares Issued Discrete item impact on effective tax rate Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Total stockholders' equity Balances, beginning Balances, ending Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Provision (benefit) for federal, state and foreign income taxes Income Tax Expense (Benefit) Accounts receivable, less allowances (March 31, 2022—$634 and June 30, 2021—$898) Accounts Receivable, after Allowance for Credit Loss, Current Equity Components [Axis] Equity Components [Axis] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Total current assets Assets, Current Intellectual Property [Member] Intellectual Property [Member] Total future operating lease payments Lessee, Operating Lease, Liability, to be Paid Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Inventories Inventory, Net Results of Operations Schedule of Segment Reporting Information, by Segment [Table Text Block] Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Entity File Number Entity File Number Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Small Business Entity Small Business Thereafter LesseeOperatingLeaseLiabilityToBePaidAfterYearFour Operating Lease, Liability, To Be Paid, After Year Four Deferred Tax Assets Generated in the Three Months Ended March 31, 2022 Deferred Tax Assets Generated in the Three Months Ended March 31, 2022 [Member] Deferred Tax Assets Generated in the Three Months Ended March 31, 2022 New Accounting Pronouncements and Changes in Accounting Principles [Abstract] Accounting Standards Update and Change in Accounting Principle [Abstract] Loss on Contracts Loss on Contracts Operating lease and fixed asset impairments due to restructuring mtrx:AdjustmentToRestructuringCostsLiability Adjustment To Restructuring Costs Liability Equity Component [Domain] Equity Component [Domain] Short-term lease expense Short-term Lease, Cost Fiscal 2023 Lessee, Operating Lease, Liability, to be Paid, Year One Foreign currency translation gain (loss) (net of tax expense (benefit) of $(16) and $30 for the three and nine months ended March 31, 2022, respectively, and $(33) and $20 for the three and nine months ended March 31, 2021, respectively) Other comprehensive income (loss) Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Asset Backed Credit Facility Federal Funds Rate Addition mtrx:AssetBackedCreditFacility_FederalFundsRateAddition mtrx:AssetBackedCreditFacility_FederalFundsRateAddition Disclosure Text Block [Abstract] Statement [Line Items] Statement [Line Items] Billings on uncompleted contracts in excess of costs and estimated earnings Increase (Decrease) in Contract with Customer, Liability Impairment of Intangible Assets, Finite-lived Impairment of Intangible Assets, Finite-lived Restricted Cash Restricted Cash, Noncurrent Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Amount Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount Reporting Unit, Percentage of Fair Value in Excess of Carrying Amount Fiscal 2026 Lessee, Operating Lease, Liability, to be Paid, Year Four Debt Disclosure [Abstract] Debt Disclosure [Abstract] Time-and-materials Contract Time-and-materials Contract [Member] Entity Address, State or Province Entity Address, State or Province Loss before income tax expense (benefit) Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Deferred Tax Assets, Valuation Allowance Deferred Tax Assets, Valuation Allowance Segment Reporting [Abstract] Segment Reporting [Abstract] Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Asset, Useful Life Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] CARES Act Deferred Payroll Tax Liability mtrx:CARESACTDeferredPayrollTaxLiability CARES ACT Deferred Payroll Tax Liability Computation of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Entity Shell Company Entity Shell Company Local Phone Number Local Phone Number Goodwill impairment and restructuring costs Restructuring, Settlement and Impairment Provisions Goodwill, Written off Related to Sale of Business Unit Goodwill, Written off Related to Sale of Business Unit Power Generation Project [Domain] Power Generation Project [Domain] [Domain] for Power Generation Project [Axis] Deferred Tax Assets, Tax Credit Carryforwards, Foreign Deferred Tax Assets, Tax Credit Carryforwards, Foreign Issuances of common stock Proceeds from Issuance of Common Stock Total assets Segment assets Assets Common stock, shares authorized Common Stock, Shares Authorized Interest, including payment of debt amendment fees Interest Paid, Excluding Capitalized Interest, Operating Activities Geographical [Domain] Geographical [Domain] Project [Axis] Power Generation Project [Axis] Power Generation Project [Axis] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Basic, by Common Class, Including Two Class Method [Table] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Deferred income tax Deferred Income Tax Expense Deferred Income Tax Expense Benefit Net cash used by operating activities Net Cash Provided by (Used in) Operating Activities Prior Year Carryback Income Tax Receivable Prior Year Carryback Income Tax Receivable Prior Year Carryback Income Tax Receivable Lease, Cost [Table Text Block] Lease, Cost [Table Text Block] Entity Tax Identification Number Entity Tax Identification Number Cash and Cash Equivalents [Line Items] Cash and Cash Equivalents [Line Items] Earnings Per Share, Basic [Abstract] Earnings Per Share, Basic [Abstract] Geographical [Axis] Geographical [Axis] Basic Weighted average shares outstanding - basic (shares) Weighted Average Number of Shares Outstanding, Basic Diluted loss per common share Diluted EPS (US$ per share) Earnings Per Share, Diluted Line of Credit Facility, Expiration Date Line of Credit Facility, Expiration Date Segments [Domain] Segments [Domain] Repayments of advances under senior secured revolving credit facility Repayments of Long-term Lines of Credit Change in net contract balances Change in net contract balances Change in net contract balances from the prior year to the current year. Income taxes Income Taxes Paid, Net Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Lease, Cost [Abstract] Lease, Cost [Abstract] Other intangible assets, net of accumulated amortization Total intangible assets, net carrying amount Intangible Assets, Net (Excluding Goodwill) Restructuring Costs [Abstract] Restructuring Costs [Abstract] Fixed-price Contract Fixed-price Contract [Member] Net cash used by financing activities Net Cash Provided by (Used in) Financing Activities Expected effective tax rate, remainder of year Expected effective tax rate, remainder of year Expected effective tax rate, remainder of year Less: Treasury stock, at cost — 1,104,952 shares as of March 31, 2022, and 1,338,779 shares as of June 30, 2021 Treasury Stock, Value Other comprehensive income (loss), net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Statement of Other Comprehensive Income [Abstract] Schedule Of Intangible Assets Excluding Goodwill Table [Text Block] Schedule Of Intangible Assets Excluding Goodwill Table [Text Block] Schedule of intangible assets excluding goodwill. Weighted average common shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Deferred income taxes Deferred Income Tax Liabilities, Net Performance obligations to be recognized as revenue within next twelve months Performance obligations to be recognized as revenue within next twelve months Performance obligations to be recognized as revenue within next twelve months. Nonvested Deferred Shares [Member] Nonvested Deferred Shares [Member] Nonvested Deferred Shares [Member] Statement Condensed Consolidated Balance Sheets [Abstract] Statement Condensed Consolidated Balance Sheets [Abstract] Statement Condensed Consolidated Balance Sheets [Abstract] Accounts payable Accounts Payable, Current Restructuring costs Restructuring Charges Accelerated amortization of deferred debt amendment fees (Note 5) Other Noncash Expense Depreciation and amortization Depreciation, Depletion and Amortization Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Percentage of real estate leases Percentage of real estate leases Percentage of leases - real estate Finite-Lived Intangible Assets, Amortization Expense, Year Three Finite-Lived Intangible Asset, Expected Amortization, Year Three Advances under senior secured revolving credit facility Proceeds from Long-term Lines of Credit Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year Inventories Increase (Decrease) in Inventories Restructuring and Related Costs [Table Text Block] Restructuring and Related Costs [Table Text Block] Cost of revenue Cost of Goods and Services Sold Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Bank of Montreal Bank of Montreal [Member] Bank of Montreal Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Total lease expense Lease, Cost Non-cash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Customer Relationships [Member] Customer Relationships [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Property, plant and equipment - net Property, Plant and Equipment, Net Claim On Power Generation Project [Member] Claim On Power Generation Project [Member] Claim On Power Generation Project [Member] Property, plant and equipment at cost: Property, Plant and Equipment, Gross [Abstract] Asset Backed Credit Facility Fixed Charge Coverage Ratio Requirement Asset Backed Credit Facility Fixed Charge Coverage Ratio Requirement Asset Backed Credit Facility Fixed Charge Coverage Ratio Requirement Lender Name [Axis] Lender Name [Axis] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired Prior federal income tax rate Prior federal income tax rate Federal income tax rate prior to the Tax Cuts and Jobs Act. Earnings Per Share [Abstract] Earnings Per Share [Abstract] Utility and Power Infrastructure Utility and Power Infrastructure [Member] Utility and Power Infrastructure. Treasury shares purchased to satisfy tax withholding obligations Other Treasury Share Purchases Other treasury share purchases. Total property, plant and equipment - at cost Property, Plant and Equipment, Gross Disclosure Customer Contracts Additional Information [Abstract] Disclosure Customer Contracts Additional Information [Abstract] Disclosure - Customer Contracts - Additional Information [Abstract] Document Quarterly Report Document Quarterly Report Other assets and liabilities Increase (Decrease) in Other Operating Assets Revenue Revenues Line of Credit Facility, Current Borrowing Capacity Line of Credit Facility, Current Borrowing Capacity Severance costs and other benefits Severance Costs Line of Credit Facility [Table] Line of Credit Facility [Table] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Restructuring costs by type [Abstract] Restructuring costs by type [Abstract] Restructuring costs by type [Abstract] Goodwill Goodwill, Gross Total future payments for lease not yet commenced Total future payments for lease not yet commenced Total future payments for lease not 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intersegment eliminations Gain on sale of property, plant and equipment Gain (Loss) on Disposition of Property Plant Equipment Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Beginning of Period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, End of Period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Costs and estimated earnings in excess of billings on uncompleted contracts Contract with Customer, Asset, after Allowance for Credit Loss, Current United States UNITED STATES Common stock, par value Common Stock, Par or Stated Value Per Share Asset Backed Credit Facility LIBOR Rate One Month Add On Asset Backed Credit Facility LIBOR Rate One Month Add On Asset Backed Credit Facility LIBOR Rate One Month Add On Current assets: Assets, Current [Abstract] Finite-Lived Intangible Assets, Gross Finite-Lived Intangible Assets, Gross Valuation Allowance by Deferred Tax Asset [Axis] Valuation Allowance by Deferred Tax Asset [Axis] Leases [Abstract] Leases [Abstract] Entity Central Index Key Entity Central Index Key Finite-Lived Intangible Assets, Remaining Amortization Period Finite-Lived Intangible Assets, Remaining Amortization Period Security Exchange Name Security Exchange Name Project Unapproved Change Orders and Claims [Table] Power Generation Project Unapproved Change Orders and Claims [Table] Power Generation Project Unapproved Change Orders and Claims [Table] Exercise of stock options, shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Diluted Diluted weighted average shares (shares) Weighted Average Number of Shares Outstanding, Diluted Income Tax Disclosure Income Tax Disclosure [Text Block] Current Fiscal Year End Date Current Fiscal Year End Date Antidilutive Securities Excluded from the Calculation of Diluted EPS Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Finite-Lived Intangible Assets, Amortization Expense, Year Five Finite-Lived Intangible Asset, Expected Amortization, Year Five Text Block [Abstract] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Other Restructuring Costs Other Restructuring Costs Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Net cash used by investing activities Net Cash Provided by (Used in) Investing Activities Disaggregation of Revenue [Abstract] Disaggregation of Revenue [Abstract] Changes in operating assets and liabilities increasing (decreasing) cash: Increase (Decrease) in Operating Capital [Abstract] Treasury shares sold to Employee Stock Purchase Plan Stock Issued During Period, Value, Employee Stock Purchase Plan Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Restriction of deductibility of certain executive compensation Restriction of deductibility of certain executive compensation Restriction of deductibility of certain executive compensation in excess of $1.0 million. Description of one of the major changes in connection with the Tax Cuts and Jobs Act of December 2017. Operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Increase (Decrease) in Income Taxes Receivable Increase (Decrease) in Income Taxes Receivable Total current liabilities Liabilities, Current Class of Stock [Domain] Class of Stock [Domain] Intersegment Eliminations [Member] Intersegment Eliminations [Member] Corporate Unallocated Corporate Costs [Member] Unallocated Corporate Costs. Construction Contractor, Receivable, Retainage, after Year One Construction Contractor, Receivable, Retainage, after Year One Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Translation adjustment Goodwill, Foreign Currency Translation Gain (Loss) Loss Contingencies [Table] Loss Contingencies [Table] Revenue from Contract with Customer Revenue from Contract with Customer, Including Assessed Tax Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Beginning equity balances, as adjusted Beginning equity balances, as adjusted Beginning equity balances as adjusted for the effects of retrospective impacts of the adoption of a new accounting standard. Entity Address, Postal Zip Code Entity Address, Postal Zip Code Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Land and buildings Buildings and Improvements, Gross Title of 12(b) Security Title of 12(b) Security Proceeds from issuance of common stock under employee stock purchase plan Proceeds from Stock Plans Other current assets Other Assets, Current Statement [Table] Statement [Table] New Accounting Pronouncements, Policy New Accounting Pronouncements, Policy [Policy Text Block] Statistical Measurement [Axis] Statistical Measurement [Axis] Issuance of deferred shares Adjustments to Additional Paid in Capital, Other Expected Remaining Amortization Expense [Abstract] Expected Remaining Amortization Expense [Abstract] Expected Remaining Amortization Expense [Abstract] Cover [Abstract] Cover [Abstract] Net Carrying Amount Finite-Lived Intangible Assets, Net Finite-Lived Intangible Assets, Net Goodwill Goodwill Net balance at June 30, 2021 Net balance at March 31, 2022 Goodwill Construction in progress Construction in Progress, Gross Operating Loss Carryforwards, Limitations on Use Operating Loss Carryforwards, Limitations on Use Schedule of Goodwill [Table Text Block] Schedule of Goodwill [Table Text Block] Other treasury shares purchases, shares Other Treasury Shares Acquired Other treasury shares acquired. Operating lease expense Operating Lease, Cost Other Information Related to Leases [Table Text Block] Other Information Related to Leases [Table Text Block] Table disclosing operating lease weighted average remaining lease term, weighted average discount rate, and supplemental cash flow disclosures. Deferred Tax Asset [Domain] Deferred Tax Asset [Domain] Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Adjustments to reconcile net loss to net cash used by operating activities: Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]