Basis of Presentation (Policies)	9 Months Ended
Basis of Presentation (Policies)	Jan. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The accompanying condensed consolidated financial statements have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (GAAP) have been condensed or omitted pursuant to such rules and regulations. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.
Reclassifications	In the opinion of management, the accompanying condensed consolidated financial statements contain all adjustments necessary to present fairly the financial position as of January 31, 2025 and April 30, 2024, the results of operations for the three and nine months ended January 31, 2025 and 2024, and shareholders' equity and cash flows for the nine months ended January 31, 2025 and 2024. Although management believes that the disclosures are adequate to make the information presented not misleading, it is suggested that these interim condensed consolidated financial statements be read in conjunction with the Company’s most recent audited financial statements and notes thereto.
New Accounting Pronouncements	In November 2024, the FASB issued ASU 2024-03, Disaggregation of Income Statement Expenses (Subtopic 220-40). The standard requires new financial statement disclosures regarding specified information about certain costs and expenses. The new standard is effective for the Company's annual periods beginning May 1, 2027, and interim periods beginning May 1, 2028, with early adoption permitted. The Company is currently evaluating ASU 2024-03 to determine its impact on our disclosures.
Revenue Recognition	The Company recognizes retail sales of prepared food and dispensed beverage, grocery and general merchandise, fuel and other revenue at the time of the sale to the guest. Sales taxes collected from guests and remitted to the government are recorded on a net basis in the condensed consolidated statements of income. A portion of revenue from sales that include points under our Casey’s Rewards program is deferred. The deferred portion of the sale represents the value of the estimated future redemption of the points. The amounts related to points are deferred until their redemption or expiration. Revenue related to the points issued is expected to be recognized less than one year from the original sale to the guest. As of January 31, 2025 and April 30, 2024, the Company recognized a contract liability of $61,810 and $52,934, respectively, primarily related to the Casey's Rewards program, which is included in accrued expenses on the condensed consolidated balance sheets. Gift card related revenue is recognized as the gift cards are used by the guest. Gift card breakage revenue is recognized based on the estimated gift card breakage rate over the pro rata usage of the card. As of January 31, 2025 and April 30, 2024, the Company recognized a liability of $20,363 and $17,985, respectively, related to outstanding gift cards, which is included in accrued expenses on the condensed consolidated balance sheets. The Company often receives vendor allowances on the basis of quantitative contract terms that vary by product and vendor or directly on the basis of purchases made. Vendor allowances include rebates and other funds received from vendors to promote their products. These amounts are recognized in the period earned based on the applicable rebate agreement. Reimbursements of an operating expense (e.g., advertising) are recorded as reductions of the related expense. Renewable identification numbers (“RINs”) are assigned to gallons of renewable fuels produced and are used to track compliance with the renewable fuel standard. At times, we purchase fuel components (ethanol, gasoline, biodiesel or diesel) and blend those components into a finished product in a fuel truck. This process enables the Company to take title to the RIN assigned to each gallon of ethanol or biodiesel produced. RINs are recorded as a reduction in cost of goods sold at the contracted sales price, in the period when the Company transfers the RIN. The Company does not record inventories on the balance sheet related to RINs, as they are acquired at no cost to the Company. The Company includes in cost of goods sold the costs incurred to acquire fuel and merchandise, including excise taxes, less vendor allowances, vendor rebates and RINs. Warehousing costs are recorded within operating expenses on the condensed consolidated statements of income.

Disclosure of accounting policy for revenue from contract with customer.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479806/606-10-50-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-19

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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-URI https://asc.fasb.org/1943274/2147479806/606-10-50-18

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/exampleRef
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-URI https://asc.fasb.org/1943274/2147483426/235-10-50-4

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/606/tableOfContent

+ Details

CASEYS GENERAL STORES INC 10-Q