Variable interest entities and other investments Variable Interest Entities and Other Investments Variable Interest Entities and Other Investments Dividends paid (in dollars per share) Common Stock, Dividends, Per Share, Cash Paid Accumulated Amortization Finite-Lived Intangible Assets, Accumulated Amortization Investments Investment, Policy [Policy Text Block] Prime Contractor Sales Channel, Directly to Consumer [Member] Award Timing Predetermined Award Timing Predetermined [Flag] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Intangible assets, gross Intangible Assets, Gross (Excluding Goodwill) Indefinite-lived Intangible Assets [Axis] Indefinite-Lived Intangible Assets [Axis] Asset Class [Axis] Asset Class [Axis] Entity File Number Entity File Number Intelligence Customers Intelligence Clients [Member] Intelligence Clients [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Interest Rate Swap Interest Rate Swap [Member] Current assets Contract with Customer, Asset, after Allowance for Credit Loss, Current [Abstract] Tabular List, Table Tabular List [Table Text Block] Supplemental Condensed Consolidated Financial Information Additional Financial Information Disclosure [Text Block] Recently Issued Accounting Pronouncements Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Accounts receivable–unbilled (contract assets) Contract with Customer, Asset, after Allowance for Credit Loss, Current Interest expense, net Interest Income (Expense), Nonoperating Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Basic (in dollars per share) Earnings Per Share, Basic Adjustment to Compensation: Adjustment to Compensation [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts payable and other accrued expenses Increase 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expense Share-Based Payment Arrangement, Noncash Expense Employee Stock Option Share-Based Payment Arrangement, Option [Member] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Dividends paid Dividends, Common Stock, Cash Total stockholders’ equity Beginning of period End of period Equity, Attributable to Parent Measurement Frequency [Axis] Measurement Frequency [Axis] OCI before reclassifications to earnings, net of income taxes OCI, before Reclassifications, Net of Tax, Attributable to Parent Other comprehensive loss, net of tax: Other Comprehensive Income (Loss), Net of Tax [Abstract] Insider Trading Policies and Procedures [Line Items] Common stock, authorized (in shares) Common Stock, Shares Authorized Hedging Designation [Domain] Hedging Designation [Domain] Increase (decrease) in income tax reserves Increase (Decrease) In Income Tax Reserves Increase (Decrease) In Income Tax Reserves Goodwill and 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[Domain] Concentration Risk Type [Domain] Net cash paid during the period for: Cash Payments Abstract Cash paid during the period for: Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Debt Instrument [Line Items] Debt Instrument [Line Items] Treasury Stock Treasury Stock, Common [Member] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Pay vs Performance Disclosure [Line Items] Investments, fair value Investment Owned, Fair Value Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Total Liabilities Financial Liabilities Fair Value Disclosure Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, 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Instrument, Interest Rate, Effective Percentage Entity Address, Postal Zip Code Entity Address, Postal Zip Code Restatement Determination Date Restatement Determination Date Cash and cash equivalents––beginning of period Cash and cash equivalents––end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement [Abstract] Income Statement [Abstract] Income tax (benefit) expense Income Tax Expense (Benefit) OCI, before reclassifications to earnings and income taxes OCI, before Reclassifications, before Tax, Attributable to Parent Fair Value, Nonrecurring Fair Value, Nonrecurring [Member] Long-term derivative instruments Derivative Liability, Noncurrent Repurchase of restricted stock Repurchase Of Stock To Satisfy Tax Withholdings, Restricted Stock, Amount Repurchase Of Stock To Satisfy Tax Withholdings, Restricted Stock, Amount Intangible assets, net of accumulated amortization Net Carrying Value Intangible Assets, Net 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Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] General and administrative expenses General and Administrative Expense Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Cost of revenue Cost of Sales [Member] Cash Flow Hedging Cash Flow Hedging [Member] Earnings Per Share, Basic and Diluted, by Common Class, Including Two Class Method [Line Items] Schedule of Earnings Per Share Basic And Diluted by Common Class [Line Items] Schedule of Earnings Per Share Basic And Diluted by Common Class Goodwill Goodwill Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] PEO Total Compensation Amount PEO Total Compensation Amount Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Money Market Funds Money Market Funds [Member] Equity Components [Axis] Equity 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Revenue [Table] Disaggregation of Revenue [Table] Senior Notes due 2029 Senior Notes Due 2029 [Member] Senior Notes Due 2029 Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Accrued retirement Liability, Pension and Other Postretirement and Postemployment Benefits, Current Deferred tax assets Deferred Income Tax Assets, Net Schedule of Accumulated Other Comprehensive Income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Purchases of property, equipment, and software Payments to Acquire Productive Assets Depreciation and amortization Depreciation, Depletion and Amortization Accrual of interest on long term receivable Increase (Decrease) in Income Taxes Receivable Other long-term assets Other Assets, Noncurrent Accrued interest Interest Payable, Current Customer [Domain] Customer [Domain] Entity Central Index Key Entity Central Index Key PEO Name PEO Name Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Fixed-price Fixed-Price Contract [Member] Revolving Credit Facility Revolving Credit Facility [Member] Arrangement Duration Trading Arrangement Duration Prepaid expenses and other current and long-term assets Increase (Decrease) in Prepaid Expense 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Credit Facility [Domain] Gross Carrying Value Finite-Lived Intangible Assets, Gross Stockholders’ equity: Equity, Attributable to Parent [Abstract] Current derivative instruments Derivative Liability, Current Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Entity Address, Address Line One Entity Address, Address Line One Repurchase of common stock Repurchase of common stock Treasury Stock, Value, Acquired, Cost Method Estimated amounts to be reclassified over 12 months Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net Accumulated Other Comprehensive Income (Loss) Total AOCI Attributable to Parent [Member] Interest Rate Debt Instrument, Interest Rate, Stated Percentage Allowance for credit losses Accounts Receivable, Allowance for Credit Loss, Current Operating lease liabilities, net of current portion Operating Lease, Liability, 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Comprehensive Income (Loss) [Line Items] Name Trading Arrangement, Individual Name All Award Types Award Type [Domain] Contract with Customer, Basis of Pricing [Domain] Contract with Customer, Basis of Pricing [Domain] Equity Awards Adjustments Equity Awards Adjustments [Member] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Compensation Amount Outstanding Recovery Compensation Amount Earnings for diluted computations Undistributed Earnings, Diluted Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Contract with customer, liability, revenue recognized Contract with Customer, Liability, Revenue Recognized Accrued compensation and benefits Increase (Decrease) in Employee Related Liabilities MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Name Awards Close in Time to MNPI Disclosures, Individual Name AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward] Cash paid and other Payments for Restructuring Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Noncash lease expense Noncash Lease Expense Noncash Lease Expense Customer contracts and related customer relationships Customer Contracts and Related Customer Relationships [Member] Customer Contracts and Related Customer Relationships Stock-based compensation expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Income taxes Other Comprehensive Income (Loss) before Reclassifications, Tax Litigation Case [Axis] Litigation Case [Axis] Statement of Income Location, Balance [Axis] Statement of Income Location, Balance [Axis] Schedule of Indefinite-Lived Intangible Assets Schedule of Indefinite-Lived Intangible Assets [Table Text Block] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Subcontractor Sales Channel, Through Intermediary [Member] Company Selected Measure Name Company Selected Measure Name Senior Notes Senior Notes [Member] Debt Debt Disclosure [Text Block] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Cost-reimbursable Cost Reimbursable Contract [Member] Cost Reimbursable Contract All Executive Categories All Executive Categories [Member] Long-term income tax receivable Income Taxes Receivable, Noncurrent Common stock, Class A - $0.01 par value - authorized: 600,000,000 shares; issued: 168,850,097 and 168,522,544 shares at June 30, 2025 and March 31, 2025, respectively; outstanding: 123,708,985 and 124,879,004 shares at June 30, 2025 and March 31, 2025, respectively Common Stock, Value, Issued Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Weighted-average common stock shares outstanding, diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Commitments and contingencies (Note 12) Commitments and Contingencies Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Senior Notes due 2035 Five Point Nine Five Percent Senior Unsecured Notes Due 2035 [Member] Five Point Nine Five Percent Senior Unsecured Notes Due 2035 Entity Small Business Entity Small Business Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Document Transition Report Document Transition Report Underlying Securities Award Underlying Securities Amount Concentration Risk [Line Items] Concentration Risk [Line Items] Billable expenses Billable Expenses Billable expenses include direct subcontractor expenses, travel expenses, and other expenses incurred to perform on contracts. 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Customers Defense Clients [Member] Defense Clients [Member] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Intangible Asset, Finite-Lived [Table] Intangible Asset, Finite-Lived [Table] Current-period OCI, net of income taxes Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Current liabilities: Liabilities, Current [Abstract] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Level 1 Fair Value, Inputs, Level 1 [Member] Revolving credit facility, amount outstanding Long-Term Line of Credit Net (gains) losses on investments, dispositions, and other Gain (Loss) on Disposition of Assets Diluted (in dollars per share) Earnings Per Share, Diluted Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Accounts receivable, net Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Title of 12(b) Security Title of 12(b) Security Senior Notes due 2033 Five Point Nine Five Percent Senior Unsecured Notes Due 2033 [Member] Five Point Nine Five Percent Senior Unsecured Notes Due 2033 Compensation Related Costs [Abstract] Compensation Related Costs [Abstract] Treasury stock (in shares) Treasury stock (in shares) Treasury stock (in shares) Treasury Stock, Common, Shares Earnings per share of common stock (Note 4): Earnings Per Share [Abstract] Earnings Per Share [Abstract] Customer [Domain] Contract with Customer, Sales Channel [Domain] Additional Financial Information Disclosure [Abstract] Additional Financial Information Disclosure Other long-term assets Contract with Customer, Asset, after Allowance for Credit Loss, Noncurrent [Abstract] Accounts Payable and Other Accrued Expenses Accounts Payable and Accrued Liabilities Disclosure [Text Block] Contract with Customer, Sales Channel [Axis] Contract with Customer, Sales Channel [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Repurchase of common stock (in shares) Repurchase of common stock (in shares) Treasury Stock, Shares, Acquired Income taxes Income Taxes Paid, Net Award Timing Disclosures [Line Items] Research and Development Tax Credits Research and Development Tax Credits [Member] Research and Development Tax Credits Outstanding Balance Long-Term Debt, Gross Measurement Frequency [Domain] Measurement Frequency [Domain] Accrued compensation and benefits Total accrued compensation and benefits Employee-related Liabilities, Current Trade name Trade Names [Member] Net income Net income Net Income (Loss) Attributable to Parent Expiration Date Trading Arrangement Expiration Date Other current and long-term liabilities Increase (Decrease) in Other Operating Liabilities Property and equipment, net of accumulated depreciation Property, Plant and Equipment, Net Severance and related charges incurred during the period Restructuring Charges Repurchases of common stock Payments for Repurchase of Common Stock Adoption Date Trading Arrangement Adoption Date Reclassification Reclassification, Comparability Adjustment [Policy Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Accounts receivable, net Increase (Decrease) in Accounts Receivable Restructuring Cost [Table] Restructuring Cost [Table] Tax Credit Carryforward [Table] Tax Credit Carryforward [Table] Entity Current Reporting Status Entity Current Reporting Status Customer [Axis] Customer [Axis] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Operating income Operating Income (Loss) Retained earnings Retained Earnings (Accumulated Deficit) Statement of Financial Position [Abstract] Statement of Financial 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Intangible Assets, Major Class Name [Domain] 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] Payables and Accruals [Abstract] Payables and Accruals [Abstract] Statement [Table] Statement [Table] Other income (expense), net Other Nonoperating Income (Expense) Adjustments to reconcile net income to net cash provided by 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] Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Advance payments, billings in excess of costs incurred and deferred revenue (contract liabilities) Contract with Customer, Liability 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 Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] All Adjustments to Compensation All Adjustments to Compensation [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Accounts payable and other accrued expenses Total accounts payable and other accrued expenses Accounts Payable and Accrued Liabilities, Current Amendment Flag Amendment Flag Treasury stock, at cost - 45,141,112 and 43,643,540 shares at June 30, 2025 and March 31, 2025 Treasury Stock, Common, Value Termination Date Trading Arrangement Termination Date Net cash used in financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Measure: Measure [Axis] Income tax reserves Liability for Uncertainty in Income Taxes, Noncurrent Weighted-average common stock shares outstanding, basic (in shares) Weighted Average Number of Shares Outstanding, Basic Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] Indefinite-Lived Intangible Assets (Excluding Goodwill) [Abstract] Cost of revenue Cost of Product and Service Sold Schedule of Reconciliation of the Income Used to Compute Basic and Diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] 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 Operating costs and expenses: Costs and Expenses [Abstract] Income taxes Reclassification from AOCI, Current Period, Tax Amounts reclassified from AOCI to earnings, before income taxes Reclassification from AOCI, Current Period, before Tax, Attributable to Parent Vendor payables Accounts Payable, Trade, Current Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, issued (in shares) Common Stock, Shares, Issued Accounting Estimates Use of Estimates, Policy [Policy Text Block] Cash dividends paid Payments of Dividends Trading Arrangement: Trading Arrangement [Axis] Current derivative instruments Derivative Asset, Current Total Shareholder Return Amount Total Shareholder Return Amount Schedule of Recurring Fair Value Measurements Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Insider Trading Arrangements [Line Items] Security Exchange Name Security Exchange Name Total liabilities Liabilities Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Product Concentration Risk Product Concentration Risk [Member] Unpaid property, equipment, and software purchases Capital Expenditures Incurred but Not yet Paid Revolving credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-Lived Intangible Assets, Major Class Name [Domain] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Other current liabilities Other Liabilities, Current Asset Class [Domain] Asset Class [Domain] Time-and-materials Time-and-Materials Contract [Member] Issuance of common stock Stock Issued During Period, Value, New Issues Statement [Line Items] Statement [Line Items] 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 equivalents, at fair value Cash and Cash Equivalent Common Stock Common Stock [Member] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] 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 Dilutive stock options and restricted stock (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment