Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Accrued retirement Liability, Pension and Other Postretirement and Postemployment Benefits, Current Non‑current unbilled receivables Business Combination, Recognized Asset Acquired, Receivable, Noncurrent Business Combination, Recognized Asset Acquired, Receivable, Noncurrent Title of 12(b) Security Title of 12(b) Security Document Fiscal Year Focus Document Fiscal Year Focus Remaining performance obligation, expected timing, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Adjustment to Compensation, Amount Adjustment to Compensation Amount Defy Security Defy Security [Member] Defy Security Customer [Axis] Customer [Axis] Common stock, Class A - $0.01 par value - authorized: 600,000,000 shares; issued: 170,513,905 and 169,805,201 shares at June 30, 2026 and March 31, 2026, respectively; outstanding: 120,284,257 and 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Income Tax Disclosure [Abstract] Concentration Risk [Line Items] Concentration Risk [Line Items] Triggering Event [Axis] Triggering Event [Axis] Triggering Event Supplemental disclosures of non-cash investing and financing activities: Noncash Investing and Financing Items [Abstract] Outstanding Balance Long-Term Debt, Gross Credit Facility [Domain] Credit Facility [Domain] Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Weighted-average common stock shares outstanding, diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Prime Contractor Sales Channel, Directly to Consumer [Member] Dividends paid (in dollars per share) Common Stock, 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Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Tabular List, Table Tabular List [Table Text Block] Intangible Asset, Finite-Lived, after Accumulated Amortization [Abstract] Intangible Asset, Finite-Lived, after Accumulated Amortization [Abstract] Other income Other Nonoperating Income (Expense) Long-term income tax receivable Income Taxes Receivable, Noncurrent Deferred income taxes and income taxes receivable/payable Increase (Decrease) in Deferred Income Taxes and Income Taxes Payable, Net of Income Taxes Receivable Increase (Decrease) in Deferred Income Taxes and Income Taxes Payable, Net of Income Taxes Receivable Schedule of Accounts Payable and Other Accrued Expenses Schedule of Accounts Payable and Accrued Liabilities [Table Text Block] Name Awards Close in Time to MNPI Disclosures, Individual Name 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] General and administrative expenses General and Administrative Expense Long-Lived Asset, Class [Domain] Long-Lived Asset, Class [Domain] Accrued payroll Accrued Bonuses, Current Adjustment to Compensation: Adjustment to Compensation [Axis] Increase To Revenue To Reflect Best Estimate Of Final Cost Rates Increase To Revenue To Reflect Best Estimate Of Final Cost Rates [Member] Increase To Revenue To Reflect Best Estimate Of Final Cost Rates Hedging Designation [Domain] Hedging Designation [Domain] Class of Stock [Domain] Class of Stock [Domain] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest Interest Paid, Excluding Capitalized Interest, Operating Activity Purchases of property, equipment, and software Payments to Acquire Productive Assets Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Hedging Designation [Axis] Hedging Designation [Axis] Non‑current accrued expenses Business Combination, Recognized Liability Assumed, Accrued Expenses, Noncurrent Business Combination, Recognized Liability Assumed, Accrued Expenses, Noncurrent Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total Assets Assets, Fair Value Disclosure Name Measure Name Income Taxes Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Aggregate purchase amount Business Combination, Consideration Transferred Additional Paid-In Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Civil and Commercial Civil and Commercial Clients [Member] Civil and Commercial Clients Indefinite-lived Intangible Assets [Axis] Intangible Asset, Indefinite-Lived, Class [Axis] Subcontractor Sales Channel, Through Intermediary [Member] Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Compensation Related Costs [Abstract] Compensation Related Costs [Abstract] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Company Selected Measure Amount Company Selected Measure Amount Depreciation and amortization Depreciation, Depletion and Amortization Number of employees Entity Number of Employees Credit Agreement Credit Agreement [Member] Credit Agreement Accrued paid time off Accrued Vacation, Current Customer [Domain] Contract with Customer, Sales Channel [Domain] Current assets: Assets, Current [Abstract] Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Income tax expense (benefit) Income Tax Expense (Benefit) Customer Concentration Risk Customer Concentration Risk [Member] Cost of revenue Cost of Product and Service Sold Award Timing Method Award Timing Method [Text Block] 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 Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Ultra I&C Mission Solutions Ultra I&C Mission Solutions [Member] Ultra I&C Mission Solutions Time-and-materials Time-and-Materials Contract [Member] Net income Net income Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Earnings for diluted computations Undistributed Earnings, Diluted Schedule of Contract Assets and Liabilities Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]