Document And Entity Information	3 Months Ended
	Jul. 31, 2014	Sep. 02, 2014
Document and Entity Information [Abstract]
Entity Registrant Name	Caseys General Stores Inc,
Document Type	10-Q
Current Fiscal Year End Date	--04-30
Entity Common Stock, Shares Outstanding		38,649,999
Amendment Flag	false
Entity Central Index Key	0000726958
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Well-known Seasoned Issuer	Yes
Document Period End Date	Jul. 31, 2014
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1