Debt Instrument, Periodic Payment, Percentage Of Principal

No definition available.

Name:	casy_DebtInstrumentPeriodicPaymentPercentageOfPrincipal
Namespace Prefix:	casy_
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Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility, Maximum Borrowing Capacity Increase

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit, Maximum Increase In Borrowing Capacity As A Percentage Of Consolidated EBITDA

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

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+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Indicates line item in statement of financial position that includes finance lease liability.

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- Definition

Amount of interest capitalized during the period.

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Balance Type:	debit
Period Type:	duration

- Definition

The net amount of operating interest income (expense).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fair value of the amount outstanding under the credit facility.

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermDebtFairValue
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Fair Value of Financial Instruments and Long Term Debt - Narrative (Details) - USD ($)		3 Months Ended	12 Months Ended
	Apr. 21, 2023	Apr. 30, 2023	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2021	Jun. 01, 2023	May 13, 2021
Debt Instrument
Long-term debt and capital lease obligations		$ 1,437,000,000	$ 1,437,000,000	$ 1,508,000,000
Finance lease liabilities (Note 7)		$ 95,072,000	$ 95,072,000	$ 74,234,000
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]		Long-term debt and finance lease obligations, net of current maturities	Long-term debt and finance lease obligations, net of current maturities	Long-term debt and finance lease obligations, net of current maturities
Interest income			$ 7,823,000	$ 48,000	$ 168,000
Capitalized interest			3,631,000	2,031,000	$ 4,537,000
Term Loan Facility \| Line of Credit
Debt Instrument
Maximum borrowing capacity							$ 300,000,000
Bank Line \| Line of Credit
Debt Instrument
Maximum borrowing capacity		$ 25,000,000	25,000,000
Bank Line \| Line of Credit \| Subsequent Event
Debt Instrument
Maximum borrowing capacity						$ 50,000,000
Line of Credit \| Revolving Credit Facility
Debt Instrument
Fair value of amount outstanding	$ 0
Line of Credit \| Letter of Credit
Debt Instrument
Maximum borrowing capacity		432,000	432,000
Line of Credit \| Term Loan Facility \| Line of Credit
Debt Instrument
Prepayment cost		15,625,000
Fair value of amount outstanding	250,000,000
Line of Credit \| New Credit Agreement Term Loan Facility
Debt Instrument
Maximum borrowing capacity	$ 250,000,000
Quarterly principal payment as a percentage	1.25%
Line of Credit \| New Credit Agreement Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument
Maximum borrowing capacity	$ 850,000,000
Line of Credit \| Credit Facilities
Debt Instrument
Maximum increase in borrowing capacity	$ 900,000,000
Maximum increase in borrowing capacity as a percentage of consolidated EBITDA	100.00%
Line of Credit \| Credit Facilities \| Secured Overnight Financing Rate
Debt Instrument
Basis spread on variable rate	0.10%
Line of Credit \| Credit Facilities \| Adjusted Daily Simple Secured Overnight Financing Rate
Debt Instrument
Basis spread on variable rate	1.00%
Line of Credit \| Credit Facilities \| Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument
Basis spread on variable rate	0.50%
Line of Credit \| Bank Line
Debt Instrument
Fair value of amount outstanding		$ 0	$ 0	$ 0
Minimum \| Line of Credit \| New Credit Agreement Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument
Facility fee percentage	0.15%
Minimum \| Line of Credit \| Credit Facilities \| Secured Overnight Financing Rate
Debt Instrument
Basis spread on variable rate	0.00%
Minimum \| Line of Credit \| Credit Facilities \| Base Rate
Debt Instrument
Basis spread on variable rate	1.10%
Minimum \| Line of Credit \| Credit Facilities \| Adjusted Daily Simple Secured Overnight Financing Rate
Debt Instrument
Basis spread on variable rate	1.00%
Minimum \| Line of Credit \| Credit Facilities \| Alternate Base Rate
Debt Instrument
Basis spread on variable rate	0.10%
Maximum \| Line of Credit \| New Credit Agreement Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument
Facility fee percentage	0.30%
Maximum \| Line of Credit \| Credit Facilities \| Base Rate
Debt Instrument
Basis spread on variable rate	1.70%
Maximum \| Line of Credit \| Credit Facilities \| Alternate Base Rate
Debt Instrument
Basis spread on variable rate	0.70%