Entity tax identification number Entity Tax Identification Number Rollovers from other plans EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Maximum Maximum [Member] 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] Selling Price EBP, Investment Sold, Excluding Plan Interest in Master Trust, Selling Price EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Table] Participant contribution, pretax, maximum, percentage EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage Self-directed brokerage fund EBP, Self-Directed Brokerage Account [Member] Total deductions EBP, Change in Net Asset Available for Benefit, Decrease Note receivable from participant, maximum borrowing amount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount Investments at Fair Value EBP, Investment, Fair Value and NAV [Text Block] Note receivable from participant, minimum borrowing amount EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount Investments, at fair value EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Level 1 Fair Value, Inputs, Level 1 [Member] Employee Benefit Plan, Investment Options, Number Employee Benefit Plan, Investment Options, Number Employee Benefit Plan, Investment Options, Number EBP, Investment, Fair Value and NAV [Abstract] Employer contribution, maximum catch-up contributions age EBP, Employer Contribution, Maximum Catch-Up Contributions Age EBP, Employer Contribution, Maximum Catch-Up Contributions Age Assets EBP, Asset [Abstract] Statistical Measurement [Axis] Statistical Measurement [Axis] Additions 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] EBP, Trustee EBP, Trustee [Member] Unfunded commitment Unfunded Commitments EBP, Fair Value, Investment, NAV, Unfunded Commitment Amendment Flag Amendment Flag 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] EBP, Description of Plan and Accounting Change [Abstract] Schedule of Investments at Fair Value EBP, Investment, Fair Value and NAV [Table Text Block] Murphy USA Inc. Murphy USA Inc. [Member] Murphy USA Inc. Common Stock Common Stock [Member] Investments [Domain] Investments [Domain] Primary residence, borrowing term EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term EBP, Note Receivable From Participant, Account, Primary Residence, Maximum Borrowing Term Use of Estimate EBP, Use of Estimate [Policy Text Block] EBP, Related Party and Party-in-Interest [Domain] EBP, Related Party and Party-in-Interest [Domain] Schedule H, Line 4i – Schedule of Assets (Held At End of Year) EBP, Schedule of Asset Held for Investment [Text Block] Cover [Abstract] Risk and Uncertainties EBP, Risk and Uncertainty [Text Block] Employer EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash EBP, Related Party and Party-in-Interest [Axis] EBP, Related Party and Party-in-Interest [Axis] Minimum Minimum [Member] 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 Revenue credits EBP, Revenue Credits EBP, Revenue Credits 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 dividend income 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] Investment Options Employee Benefit Plan, Investment Options [Text Block] Employee Benefit Plan, Investment Options 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] Common stocks 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] Redemption restriction, period in effect EBP, Fair Value, Investment, NAV, Redemption Restriction, Period in Effect Administrative expense EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Total EBP, Asset Held for Investment Document Information [Line Items] Document Information [Line Items] Net assets available for benefits: EBP, Change in Net Asset Available for Benefit, Increase (Decrease) [Abstract] EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Line Items] EBP, Risk and Uncertainty [Table] EBP, Risk and Uncertainty [Table] Participant compensation matched, percentage EBP, Employer Contribution, Participant Compensation Matched, Percentage EBP, Statement of Change in Net Asset Available for Benefit [Abstract] EBP, Tax Status [Table] EBP, Tax Status [Table] Net increase for the year EBP, Change in Net Asset Available for Benefit, Increase (Decrease) Related-Party Transactions EBP, Related Party and Party-in-Interest Transactions [Text Block] EBP, Related Party and Party-in-Interest Transactions [Abstract] EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract] Employer contributions receivable EBP, Employer Contribution, Receivable Automatic deferral rate EBP, Participant Contribution, Automatic, Deferral Rate Increase from dividend income on investment EBP, Change in Net Asset Available for Benefit, Increase from Dividend Income on Investment Benefits paid to participants EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Current value EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Current Value Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] EBP, Statement of Net Asset Available for Benefit [Abstract] General loan, borrowing term EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term EBP, Note Receivable From Participant, General Loan, Maximum Borrowing Term EBP, Accounting Policy [Line Items] EBP, Accounting Policy [Line Items] Investment Fund [Axis] Investment Fund [Axis] Investment Fund EBP, Tax Status [Abstract] Participant loan, current value EBP, Asset Held for Investment, Participant Loan, after Deemed Distribution Investment Valuation and Income Recognition EBP, Investment [Policy Text Block] Participant contributions receivable 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] Document Type Document Type Net Assets and Investments Employee Benefit Plan, Net Assets and Investments [Text Block] Employee Benefit Plan, Net Assets and Investments Entity Central Index Key Entity Central Index Key Participant loan, interest rate EBP, Asset Held for Investment, Participant Loan, Interest Rate Common/collective trusts Common Collective Trust [Member] EBP, Tax Status [Line Items] EBP, Tax Status [Line Items] EBP, Risk and Uncertainty [Abstract] Deductions EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Schedule of Net Assets Schedule of Net Assets [Table Text Block] Schedule of Net Assets Notes receivable from participants EBP, Note Receivable from Participant Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Murphy Oil Corporation Murphy Oil Corporation [Member] Murphy Oil Corporation Summary of Significant Accounting Policies EBP, Summary of Accounting Policy [Text Block] Entity Registrant Name Entity Registrant Name Cost of Asset EBP, Investment Acquired, Excluding Plan Interest in Master Trust, Cost Income Taxes EBP, Tax Status [Text Block] Investment Fund [Domain] Investment Fund [Domain] Investment Fund [Domain] Note receivable from participant, maximum borrowing percentage EBP, Note Receivable from Participant, Account, Maximum Borrowing, to Total Account, Percentage Document Information [Table] Document Information [Table] Note 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 Redemption, notice period EBP, Fair Value, Investment, NAV, Redemption, Notice Period EBP 001 EBP 001 [Member] EBP 001 EBP, Related Party and Party-in-Interest Transactions [Line Items] EBP, Related Party and Party-in-Interest Transactions [Line Items] Participant compensation matched, minimum service period EBP, Requisite Service Period EBP, Requisite Service Period Net assets available for benefits Beginning of year End of year EBP, Net Asset Available for Benefit Entity [Domain] Entity [Domain] Contributions: EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] NAV 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]