Disposal Group Name [Domain] Disposal Group Name [Domain] Entity tax identification number Entity Tax Identification Number Participant rollovers EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Maximum Maximum [Member] Change in deemed distributions of participant loans including defaulted loans EBP, Reconciliation to Form 5500, Change in Net Asset Available for Benefit, Increase (Decrease) from Deemed Distribution Legal Entity [Axis] Legal Entity [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] EBP, Description of Plan [Table] EBP, Description of Plan [Table] Mutual funds Mutual Fund [Member] EBP, Accounting Standard Update and Change in Accounting Principle [Table] EBP, Accounting Standard Update and Change in Accounting Principle [Table] EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Fully Benefit-Responsive Investment Contract [Table] EBP, Fully Benefit-Responsive Investment Contract [Table] Total deductions EBP, Change in Net Asset Available for Benefit, Decrease Maximum borrowing amount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount Fair Value Measurements EBP, Investment, Fair Value and NAV [Text Block] Minimum borrowing amount EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount EBP, Fully Benefit-Responsive Investment Contract [Abstract] Total assets measured at fair value EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Amount credited to participant accounts, accrued but not paid EBP, Employer Contribution, Amount Credited To Participant Accounts, Accrued But Not Paid EBP, Employer Contribution, Amount Credited To Participant Accounts, Accrued But Not Paid EBP, Employer Contribution, Type [Axis] EBP, Employer Contribution, Type [Axis] EBP, Employer Contribution, Type Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Automatic deferral rate, annual increase EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate EBP, Participant Contribution, Automatic, Annual Increase Deferral Rate Disposal Group Name [Axis] Disposal Group Name [Axis] EBP, Reconciliation of Financial Statement to Form 5500 EBP, Reconciliation of Financial Statement to Form 5500 [Table Text Block] EBP, Investment, Fair Value and NAV [Abstract] EBP, Discretionary Profit Sharing Contribution EBP, Discretionary Profit Sharing Contribution [Member] EBP, Discretionary Profit Sharing Contribution Net increase in net assets available for benefits after transfer Net increase in net assets available for benefits after transfer EBP, Change in Net Asset Available for Benefit, Including Plan Transfers, Increase (Decrease) EBP, Change in Net Asset Available for Benefit, Including Plan Transfers, Increase (Decrease) Assets: EBP, Asset [Abstract] Statistical Measurement [Axis] Statistical Measurement [Axis] Additions to Net Assets Attributed to: EBP, Change in Net Asset Available for Benefit, Increase [Abstract] EBP, Statement of Change in Net Asset Available for Benefit [Table] EBP, Statement of Change in Net Asset Available for Benefit [Table] Distributions to Participants EBP, Payment to Participant [Policy Text Block] Plan transfers Plan transfers EBP, Change in Net Asset Available for Benefit, Transfer to (from) Plan Vanguard Institutional Index Fund EBP, Vanguard Institutional Index Fund [Member] EBP, Vanguard Institutional Index Fund Amendment Flag Amendment Flag EBP, Dividends Paid EBP, Dividends Paid [Member] EBP, Dividends Paid Deemed distributions of participant loans Deemed distributions of participant loans EBP, Reconciliation to Form 5500, Net Asset Available for Benefit, Deemed Distribution Basis of Accounting EBP, Basis of Accounting [Policy Text Block] EBP, Schedule of Asset Held for Investment [Table] EBP, Schedule of Asset Held for Investment [Table] Investment number of shares (in shares) EBP, Investment, Number of Shares EBP, Description of Plan and Accounting Change [Abstract] Receivables: EBP, Receivable [Abstract] EBP, Investment, Fair Value and NAV EBP, Investment, Fair Value and NAV [Table Text Block] Disposal Group Classification [Axis] Disposal Group Classification [Axis] Minimum age to be eligible to participate EBP, Minimum Age of Participant EBP, Minimum Age of Participant Common stock Common Stock [Member] Investments [Domain] Investments [Domain] EBP, Nonemployer, Common Stock EBP, Nonemployer, Common Stock [Member] Use of Estimates EBP, Use of Estimate [Policy Text Block] Schedule H, Line 4i – Schedule of Assets (Held At End of Year) EBP, Schedule of Asset Held for Investment [Text Block] Cover [Abstract] Discontinued Operations, Disposed of by Means Other than Sale, Spinoff Discontinued Operations, Disposed of by Means Other than Sale, Spinoff [Member] Employers EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash Summary of Concentration of Investments EBP, Risk and Uncertainty [Table Text Block] Minimum Minimum [Member] Dividends EBP, Investment Income, Receivable Investment Type [Axis] Investment Type [Axis] Interest income on notes receivable from participants EBP, Change in Net Asset Available for Benefit, Increase from Interest Income on Note Receivable from Participant Total contributions EBP, Change in Net Asset Available for Benefit, Increase from Contribution Fidelity 500 Index Fund EBP, Fidelity 500 Index Fund [Member] EBP, Fidelity 500 Index Fund Participants EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover Net appreciation in fair value of investments EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment Interest and dividends EBP, Change in Net Asset Available for Benefit, Increase from Interest and Dividend Income on Investment EBP, Description of Plan [Line Items] EBP, Description of Plan [Line Items] Plan number EBP, Plan Number EBP, Investment, Fair Value and NAV [Line Items] EBP, Investment, Fair Value and NAV [Line Items] Description of the Plan EBP, Description of Plan [Text Block] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Schedule of Asset Held for Investment [Line Items] EBP, Schedule of Asset Held for Investment [Line Items] Contributions EBP, Contribution [Policy Text Block] MDU Resources Common Stock Common Stock EBP, Employer, Common Stock [Member] EBP, Schedule of Asset Held for Investment [Abstract] EBP, Accounting Policy [Table] EBP, Accounting Policy [Table] Total additions EBP, Change in Net Asset Available for Benefit, Increase Investment income: EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment [Abstract] Investment, Identifier [Axis] Investment, Identifier [Axis] Administrative expenses EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Assets held for investment EBP, Asset Held for Investment EBP, Schedule of Asset Acquired and Disposed of within Year [Table] EBP, Schedule of Asset Acquired and Disposed of within Year [Table] Risks and Uncertainties EBP, Risk and Uncertainty [Policy Text Block] Document Information [Line Items] Document Information [Line Items] EBP, Statement of Change in Net Asset Available for Benefit [Abstract] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Disposal Group Classification [Domain] Disposal Group Classification [Domain] EBP, Employer Contribution, Type [Domain] EBP, Employer Contribution, Type [Domain] EBP, Employer Contribution, Type [Domain] Vesting period EBP, Employer Contribution Vesting Service Period EBP, Employer Contribution Vesting Service Period Vesting percentage EBP, Employer Contribution Vesting Percentage EBP, Employer Contribution Vesting Percentage Total net gain per the Form 5500 EBP, Form 5500 Caption, Net Income (Loss) Stock split, conversion ratio EBP, Disposal Group, Including Discontinued Operation, Stock Split, Conversion Ratio EBP, Disposal Group, Including Discontinued Operation, Stock Split, Conversion Ratio EBP, Fully Benefit-Responsive Investment Contract [Line Items] EBP, Fully Benefit-Responsive Investment Contract [Line Items] EBP, Tax Status [Table] EBP, Tax Status [Table] Net increase in net assets available for benefits prior to transfer EBP, Change in Net Asset Available for Benefit, Increase (Decrease) Related-Party and Exempt Party-In-Interest Transactions EBP, Related Party and Party-in-Interest Transactions [Text Block] T Rowe Price Large-Cap Growth Fund EBP, T Rowe Price Large-Cap Growth Fund [Member] EBP, T Rowe Price Large-Cap Growth Fund EBP, Related Party and Party-in-Interest Transactions [Abstract] EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract] Total receivables EBP, Receivable Employer contributions EBP, Employer Contribution, Receivable Automatic deferral rate EBP, Participant Contribution, Automatic, Deferral Rate Investments (participant-directed): EBP, Investment, Fair Value [Abstract] EBP, Schedule of Asset Acquired and Disposed of within Year [Line Items] EBP, Schedule of Asset Acquired and Disposed of within Year [Line Items] Distributions to participants EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Dividends from Company stock EBP, Change in Net Asset Available for Benefit, Increase from Dividend Income on Investment Total investments EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Current Value Investment Contract with Insurance Company EBP, Investment [Text Block] EBP, Investment Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Everus Everus [Member] Everus Elected contribution percentage increment EBP, Investment, Elected Contribution Percentage Increment EBP, Investment, Elected Contribution Percentage Increment EBP, Statement of Net Asset Available for Benefit [Abstract] Fees and commissions associated with investments other than common stock EBP, Fees And Commissions Associated With Investments Other Than Common Stock EBP, Fees And Commissions Associated With Investments Other Than Common Stock EBP, Accounting Policy [Line Items] EBP, Accounting Policy [Line Items] EBP, Tax Status [Abstract] EBP, Reconciliation of Financial Statement to Form 5500 [Table] EBP, Reconciliation of Financial Statement to Form 5500 [Table] Cash EBP, Noninterest-Bearing Cash EBP, Reconciliation of Financial Statement to Form 5500 [Line Items] EBP, Reconciliation of Financial Statement to Form 5500 [Line Items] Amount credited to participant accounts EBP, Employer Contribution, Amount Credited To Participant Accounts EBP, Employer Contribution, Amount Credited To Participant Accounts Administrative Expenses EBP, Expense [Policy Text Block] Reconciliation of Financial Statements to Form 5500 EBP, Reconciliation of Financial Statement to Form 5500 [Text Block] Participant Loan Funds EBP, Asset Held for Investment, Participant Loan, after Deemed Distribution Investment Valuation and Income Recognition EBP, Investment [Policy Text Block] Participant contributions EBP, Participant Contribution, Receivable Fair Value, Inputs, Level 1, Level 2, and Level 3 Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member] EBP, Accounting Standard Update and Change in Accounting Principle [Line Items] EBP, Accounting Standard Update and Change in Accounting Principle [Line Items] Document Type Document Type EBP, Schedule of Asset Acquired and Disposed of within Year [Abstract] Revenue-sharing adjustments, fee levelization EBP, Revenue-Sharing Adjustment, Fee Levelization EBP, Revenue-Sharing Adjustment, Fee Levelization Entity Central Index Key Entity Central Index Key Participant loan, interest rate EBP, Asset Held for Investment, Participant Loan, Interest Rate EBP, Reconciliation of Financial Statement to Form 5500 [Abstract] Collective trust fund investments measured at net asset value Common Collective Trust [Member] EBP, Tax Status [Line Items] EBP, Tax Status [Line Items] EBP, Subsequent Event [Table] EBP, Subsequent Event [Table] Deductions from Net Assets Attributed to: EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Forfeited nonvested account, decrease from employer contribution EBP, Forfeited Nonvested Account, Decrease from Employer Contribution Flexible installment period, maximum EBP, Distributions to Participants, Flexible Installments, Period, Maximum EBP, Distributions to Participants, Flexible Installments, Period, Maximum Notes receivable from participants EBP, Note Receivable from Participant Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Summary of Significant Accounting Policies EBP, Summary of Accounting Policy [Text Block] Entity Registrant Name Entity Registrant Name Amount EBP, Risk and Uncertainty, Concentration of Investment at Fair Value to Net Assets, Amount Percent of net assets EBP, Risk and Uncertainty, Concentration of Investment at Fair Value to Net Assets, Percentage Distributions to participants, requested prior to year end but not paid EBP, Distributions To Participants, Requested Prior To Year End But Not Paid EBP, Distributions To Participants, Requested Prior To Year End But Not Paid EBP, Subsequent Event [Abstract] Subsequent Events EBP, Subsequent Event [Text Block] Maximum annual compensation to total compensation, percentage EBP, Participant Contribution, Maximum Contribution to Eligible Compensation, Percentage EBP, Participant Contribution, Maximum Contribution to Eligible Compensation, Percentage Federal Income Taxes EBP, Tax Status [Text Block] Maximum borrowing, percentage EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage EBP, Subsequent Event [Line Items] EBP, Subsequent Event [Line Items] EBP 004 EBP 004 [Member] EBP 004 Document Information [Table] Document Information [Table] Notes Receivable from Participants EBP, Note Receivable from Participant [Policy Text Block] Total investment income EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment EBP, Related Party and Party-in-Interest Transactions [Line Items] EBP, Related Party and Party-in-Interest Transactions [Line Items] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Other EBP, Other Receivable Net assets available for benefits Net assets available for benefits at beginning of year Net assets available for benefits at end of year Net assets available for benefits per the financial statements EBP, Net Asset Available for Benefit EBP, Investment, Excluding Plan Interest in Master Trust, Fair and Contract Value EBP, Investment, Excluding Plan Interest in Master Trust, Fair and Contract Value Entity [Domain] Entity [Domain] Contributions: EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] Fully benefit-responsive investment contract, at contract value EBP, Investment, Excluding Plan Interest in Master Trust, Contract Value Forfeited nonvested account, balance EBP, Forfeited Nonvested Account Net assets available for benefits per the Form 5500 EBP, Form 5500 Caption, Net Assets Fair Value Measured at Net Asset Value Per Share Fair Value Measured at Net Asset Value Per Share [Member] EBP, Investment, Fair Value and NAV [Table] EBP, Investment, Fair Value and NAV [Table] EBP, Statement of Net Asset Available for Benefit [Line Items] EBP, Statement of Net Asset Available for Benefit [Line Items]