Long-term Debt and Finance Lease Obligations, Lines of Credit and Fair Value Disclosure - Narrative (Details) - USD ($)		3 Months Ended
	Oct. 30, 2024	Jul. 31, 2025	Jul. 31, 2024	Apr. 30, 2025
Debt Instrument
Fair value of long-term debt		$ 2,267,000,000		$ 2,285,000,000
Finance lease obligations		110,829,000		108,920,000
Interest income		2,977,000	$ 2,385,000
Capitalized interest		495,000	$ 419,000
Credit Facilities \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Line of Credit
Debt Instrument
Basis spread on variable rate	0.10%
Credit Facilities \| Revolving Credit Facility \| Federal Funds \| Line of Credit
Debt Instrument
Basis spread on variable rate	0.50%
Credit Facilities \| Revolving Credit Facility \| Daily Simple Secured Overnight Financing Rate \| Line of Credit
Debt Instrument
Basis spread on variable rate	1.00%
Credit Facilities \| Minimum \| Revolving Credit Facility \| Secured Overnight Financing Rate (SOFR) \| Line of Credit
Debt Instrument
Basis spread on variable rate	0.00%
Credit Facilities \| Minimum \| Revolving Credit Facility \| Base Rate \| Line of Credit
Debt Instrument
Basis spread on variable rate	1.10%
Credit Facilities \| Minimum \| Revolving Credit Facility \| Daily Simple Secured Overnight Financing Rate \| Line of Credit
Debt Instrument
Basis spread on variable rate	0.10%
Credit Facilities \| Maximum \| Revolving Credit Facility \| Base Rate \| Line of Credit
Debt Instrument
Basis spread on variable rate	1.70%
Credit Facilities \| Maximum \| Revolving Credit Facility \| Daily Simple Secured Overnight Financing Rate \| Line of Credit
Debt Instrument
Basis spread on variable rate	0.70%
Unsecured Revolving Credit Facility Due January 2024 \| Revolving Credit Facility
Debt Instrument
Maximum borrowing capacity		850,000,000
Fair value of amount outstanding		0		0
Unsecured Revolving Line of Credit \| Line of Credit
Debt Instrument
Maximum borrowing capacity		50,000,000
Fair value of amount outstanding		0		$ 0
Unsecured Revolving Line of Credit \| Letter of Credit
Debt Instrument
Maximum borrowing capacity		$ 274,000

CASEYS GENERAL STORES INC 10-Q