Description of Business and Basis of Presentation	3 Months Ended
Description of Business and Basis of Presentation	Mar. 31, 2026
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation Description of business — Murphy USA Inc. and its consolidated subsidiaries (“Murphy USA”, "we", "our", "us", or the “Company”) markets refined products through a network of retail gasoline stores and to unbranded wholesale customers. The Company owns and operates a chain of retail stores under the brand names of Murphy USA® and Murphy Express, most of which are located in close proximity to Walmart stores, and also has a mix of convenience stores with and without retail gasoline that operate under the brand name of QuickChek®. At March 31, 2026, the Company had a total of 1,803 Company stores of which 1,655 were branded as Murphy and 148 were the QuickChek brand. The Company also has certain fuel supply assets, including product distribution terminals and pipeline positions. Basis of Presentation — Murphy USA was incorporated in March 2013 and, in connection with its incorporation, Murphy USA issued 100 shares of common stock, par value $0.01 per share, to Murphy Oil Corporation (“Murphy Oil”) for $1.00. On August 30, 2013, Murphy USA was separated from Murphy Oil through the distribution of 100% of the common stock of Murphy USA to holders of Murphy Oil stock. Murphy USA Inc., Murphy Oil USA, Inc. and its subsidiaries operate on a calendar year basis. In preparing the financial statements of Murphy USA in conformity with accounting principles generally accepted in the United States, management has made a number of estimates and assumptions related to the reporting of assets, liabilities, revenues, expenses and the disclosure of contingent assets and liabilities. Actual results may differ from these estimates. The Company does not have any components of comprehensive income and comprehensive income is equal to net income (loss) reported in the Consolidated Statements of Income for all periods presented. Interim Financial Information — The interim period financial information presented in these consolidated financial statements is unaudited and includes all known accruals and adjustments, in the opinion of management, necessary for a fair presentation of the consolidated financial position of Murphy USA and its results of operations and cash flows for the periods presented. All such adjustments are of a normal and recurring nature. These interim consolidated financial statements should be read together with our audited financial statements for the years ended December 31, 2025, 2024 and 2023, included in our Annual Report on Form 10-K (File No. 001-35914), as filed with the Securities and Exchange Commission under the Securities Exchange Act of 1934 on February 18, 2026. Recently Issued Accounting Standards— In November 2024, the FASB issued ASU 2024-03, "Disaggregation of Income Statement Expenses." This ASU addresses investor requests for more granular information about an entity’s expenses, allowing investors to better understand performance, prospects for future cash flows, and comparability over time and with other entities. The primary goal is to improve the decision-usefulness of expense information on public companies’ income statements through disaggregation of relevant expense captions in the notes to the financial statements. The amendments in this update are effective for the Company for annual periods beginning after December 15, 2026, and interim periods in the year beginning after December 15, 2027. Early adoption is permitted. The amendments should be applied either prospectively or retrospectively. The Company is assessing the impact of the standard on the Company's consolidated financial statements. In November 2025, the FASB issued ASU 2025-09, “Derivatives and Hedging (Topic 815)—Hedge Accounting Improvements.” This ASU is intended to more closely align financial reporting with the economics of some of an entity’s risk management activities. The changes are in response to stakeholder feedback from implementing ASU 2017-12 and the effects of LIBOR cessation. The main amendments relate to cash flow hedging, but some of the amendments affect certain fair value and net investment hedges. The amendments will be effective for annual reporting periods beginning after December 15, 2026, and interim reporting periods within those annual reporting periods. Early adoption is permitted, and the amendments are to be applied prospectively. The Company is currently assessing the impact of the standard on the consolidated financial statements. In December 2025, the FASB issued ASU 2025-11, "Interim Reporting (Topic 270)—Narrow-Scope Improvements". This ASU clarifies the interim reporting requirements by improving navigability of Topic 270 and more clearly specifying what disclosures are required in an interim reporting period. It is not intended to significantly change interim reporting or expand or reduce interim disclosure requirements. The amendments will be effective for interim reporting periods beginning after December 15, 2027. Early adoption is permitted, and the amendments may be applied either prospectively or retrospectively. The Company is currently evaluating the impact of the standard on the consolidated financial statements and does not expect the adoption to have a material impact. In December 2025, the FASB issued ASU 2025-12, "Codification Improvements". This ASU focuses on clarifying guidance, correcting unintended errors and making minor editorial refinements across the Codification and is not expected to have a significant effect on accounting practices. The amendments are effective for annual and interim periods in fiscal years beginning after December 15, 2026. Early adoption is permitted. Most amendments may be applied prospectively or retrospectively, except for the Topic 260 (earnings per share) amendments, which require retrospective application. The Company is currently evaluating the impact of the standard on the consolidated financial statements and does not expect the adoption to have a material impact.