v3.22.2.2
Cover Page - shares
 3 Months Ended
Jul. 31, 2022
Sep. 01, 2022
Cover [Abstract]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jul. 31, 2022  
Document Transition Report false  
Entity File Number 001-34700  
Entity Registrant Name CASEY’S GENERAL STORES, INC.  
Entity Incorporation, State or Country Code IA  
Entity Tax Identification Number 42-0935283  
Entity Address, Address Line One One SE Convenience Blvd  
Entity Address, City or Town Ankeny  
Entity Address, State or Province IA  
Entity Address, Postal Zip Code 50021  
City Area Code 515  
Local Phone Number 965-6100  
Title of 12(b) Security Common Stock, no par value per share  
Trading Symbol CASY  
Security Exchange Name NASDAQ  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding (in shares)   37,255,085
Entity Central Index Key 0000726958  
Current Fiscal Year End Date --04-30  
Document Fiscal Year Focus 2023  
Document Fiscal Period Focus Q1  
Amendment Flag false