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Management Reimbursement Revenue [Member] Company Selected Measure Name Company Selected Measure Name Contract Types and Contract Balances Revenue [Policy Text Block] CREDIT FACILITY Debt Disclosure [Text Block] Preferred stock, $0.01 par value; 500,000 shares authorized; none issued Preferred Stock, Value, Issued Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Trade accounts payable Accounts Payable, Current Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Liabilities assumed Business Combination, Recognized Liability Assumed, Liability All Executive Categories All Executive Categories [Member] Stockholders' Equity Note [Abstract] Common stock, $0.01 par value; 100,000,000 shares authorized; 58,580,923 and 60,176,611 shares issued and outstanding at April 30, 2026 and October 31, 2025, respectively Common Stock, Value, Issued Liability for Claims and Claims Adjustment Expense [Table] Liability for Claims and Claims Adjustment 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[Member] RavenVolt, Inc. 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Erroneous Compensation Analysis [Text Block] Current liabilities Liabilities, Current [Abstract] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Raul Valentin [Member] Rene Jacobsen Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Fair Value, Inputs, Level 1 Fair Value, Inputs, Level 1 [Member] Gain on sale of assets Gain (Loss) on Disposition of Assets Diluted (in USD per share) Earnings Per Share, Diluted Janitorial Facility Service Line, Janitorial [Member] Janitorial [Member] Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Title of 12(b) Security Title of 12(b) Security Amortization of previously capitalized contract costs Capitalized Contract Cost, Amortization Other comprehensive income Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Net income per common share Earnings Per Share [Abstract] Earnings Per Share [Abstract] Long-term lease liabilities Increase (Decrease) In Lease Liabilities, Noncurrent Increase (Decrease) In Lease Liabilities, Noncurrent Consolidation Items [Domain] Consolidation Items [Domain] Schedule of Anti-Dilutive Outstanding Stock Awards Issued Under Share-Based Compensation Plans Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Self insurance retention amount per-claim Self Insured Retention, Amount Per Occurrence Self Insured Retention, Amount Per Occurrence Operating cash outflow amount of contingent consideration payment Payment for Contingent Consideration Liability, Operating Activities Indirect costs Cost, Indirect Cost, Indirect Effect of dilutive securities Weighted Average Number of Shares Outstanding, Diluted, Adjustment [Abstract] Education Education [Member] Education [Member] Scenario, Material Acquisition Scenario, Plan [Member] Award Timing Disclosures [Line Items] Measurement Frequency [Domain] Measurement Frequency [Domain] Accrued compensation Employee-related Liabilities, Current Property, plant and equipment, net of accumulated depreciation of $404.5 and $379.8 at April 30, 2026 and October 31, 2025, respectively Property, Plant, and Equipment and Finance Lease Right-of-Use Asset, after Accumulated Depreciation and Amortization Interest Rate Swap, Effective 2/25/2022 Interest Rate Swap, Effective 2/25/2022 [Member] Interest Rate Swap, Effective 2/25/2022 COMMON STOCK Equity [Text Block] Net income Net income Net income Net Income (Loss) Attributable to Parent Expiration Date Trading Arrangement Expiration Date Pending Litigation Pending Litigation [Member] Instruments Used to Collateralize Insurance Obligations, Type [Domain] Instruments Used to Collateralize Insurance Obligations, Type [Domain] Instruments Used to Collateralize Insurance Obligations, Type [Domain] Other accrued liabilities Other Accrued Liabilities, Current Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Restructuring and related expenses Restructuring charges recognized Costs recognized Restructuring Charges Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Repurchases of common stock, including excise taxes Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Restructuring Cost [Table] Restructuring Cost [Table] Entity Current Reporting Status Entity Current Reporting Status Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Revenue from External Customers by Products and Services [Table] Segment Reporting, Revenue from External Customer, Product and Service [Table] Operating profit Operating Income (Loss) Line of Credit Line of Credit [Member] Building & Energy Solutions Engineering And Infrastructure Service Line, Building And Energy Solutions [Member] Building & Energy Solutions [Member] Retained earnings Retained Earnings (Accumulated Deficit) Noncurrent insurance claims Self Insurance Reserve, Noncurrent Schedule of Repurchase Activity Class of Treasury Stock [Table Text Block] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Executive Category: Executive Category [Axis] Right-of-use assets Increase (Decrease) In Operating Lease Right-Of-Use Asset Increase (Decrease) In Operating Lease Right-Of-Use Asset Borrowings from debt Proceeds from Issuance of Long-Term Debt Current Fiscal Year End Date Current Fiscal Year End Date Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Consulting and professional services Professional Fees Statement [Table] Statement [Table] Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Deferred income taxes Deferred Income Tax Expense (Benefit) Adjustments to reconcile net income to net cash provided by (used in) operating activities Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] Cash flows from financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Total noncurrent portion of term loan Loans Payable, Noncurrent Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Net assets acquired Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill Operating profit Segment Reporting Information, Profit (Loss) [Abstract] Distributions from unconsolidated affiliates Proceeds from Equity Method Investment, Distribution BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Insurance claims Increase (Decrease) in Self Insurance Reserve Anti-dilutive (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Weighted-average common and common equivalent shares outstanding Weighted Average Number of Shares Outstanding, Diluted [Abstract] All Adjustments to Compensation All Adjustments to Compensation [Member] Asset Impairment Asset Impairment [Member] Asset Impairment Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Amendment Flag Amendment Flag Salaries and wages (other than direct) Salary and Wage, Excluding Cost of Good and Service Sold 2027 Long-Term Debt, Maturity, Year Two Termination Date Trading Arrangement Termination Date Net cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Unamortized deferred financing costs Debt Issuance Costs, Noncurrent, Net Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Long-term debt Long-Term Debt, Excluding Current Maturities [Abstract] Revenues attributable to acquiree Business Combination, Acquiree's Revenue since Acquisition Date, Actual Selling Selling Expense Basic (in shares) Weighted-average common and common equivalent shares outstanding — Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Amount of authorized repurchases remaining under share repurchase program Share Repurchase Program, Remaining Authorized, Amount Operating expenses Cost of Product and Service Sold Primary policy limit Workers Compensation, General Liability, And Other Insurable Risks, Insurance Policy Limit Represents the policy limit provided by the insurance program for workers' compensation, general liability, and other insurable risks. Schedule of Basic and Diluted Net Income Per Common Share Calculations Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Insurance deposits Restricted Cash and Cash Equivalent, Noncurrent Segment Reporting [Abstract] Segment Reporting [Abstract] Impairment loss recorded on costs capitalized Capitalized Contract Cost, Impairment Loss Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Entity Tax Identification Number Entity Tax Identification Number Scenario [Domain] Scenario [Domain] Schedule of Insurance Related Balances and Activity Schedule Of Insurance Related Balances And Activity [Table Text Block] Schedule Of Insurance Related Balances And Activity [Table Text Block] Surety bonds and surety-backed letters of credit Surety Bonds And Surety-Backed Letters Of Credit [Member] Surety Bonds And Surety-Backed Letters Of Credit Other significant segment items Segment Reporting Information, Additional Information [Abstract] Restructuring and Related Activities [Abstract] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Common stock, par value (in USD per share) Common Stock, Par or Stated Value Per Share Common stock, shares issued (in shares) Common Stock, Shares, Issued Number of industry groups Number Of Industry Groups Number Of Industry Groups 2029 Long-Term Debt, Maturity, Year Four Parking and Transportation Facility Service Line, Parking And Transportation [Member] Facility Services, Parking and Transportation Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Income tax benefit Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Interest expense Interest Expense, Nonoperating Trading Arrangement: Trading Arrangement [Axis] Income taxes payable, net Increase (Decrease) in Income Taxes Payable Total Shareholder Return Amount Total Shareholder Return Amount Loss Contingencies [Line Items] Loss Contingencies [Line Items] Insider Trading Arrangements [Line Items] Corporate Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] Security Exchange Name Security Exchange Name M&D Manufacturing And Distribution [Member] Unbilled trade receivables Contract With Customer, Asset, Unbilled Trade Receivables, Current Contract With Customer, Asset, Unbilled Trade Receivables, Current Contract with Customer, Liabilities [Roll Forward] Contract with Customer, Liabilities [Roll Forward] Contract with Customer, Liabilities [Roll Forward] Total liabilities Liabilities Interest Rate Swap, Effective 7/7/2022 Interest Rate Swap, Effective 7/7/2022 [Member] Interest Rate Swap, Effective 7/7/2022 Line of credit facility, borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Number of customers retained Business Combination, Contingent Consideration, Number Of Customers Retained Business Combination, Contingent Consideration, Number Of Customers Retained Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Pledging Purpose [Axis] Pledging Purpose [Axis] Repurchase of common stock, including excise tax (in shares) Total number of shares purchased (in shares) Stock Repurchased During Period, Shares Prepaid expenses Prepaid Expense, Current Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Operations and Maintenance Engineering And Infrastructure Service Line, Operations And Maintenance [Member] Operations and Maintenance [Member] Statement [Line Items] Statement [Line Items] Consolidation Items [Axis] Consolidation Items [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and cash equivalents Cash and Cash Equivalent Tax to be reclassified during the next 12 months Interest Rate Cash Flow Hedge Gain (Loss) To Be Reclassified During Next 12 Months, Tax Interest Rate Cash Flow Hedge Gain (Loss) To Be Reclassified During Next 12 Months, Tax Common Stock Common Stock [Member] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Net decrease in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation