Share-based Compensation Arrangement By Share-based Payment Award, Equity Instruments Other Than Options, Granted In Period, Total Fair Value

No definition available.

+ Details

Name:	casy_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedInPeriodTotalFairValue
Namespace Prefix:	casy_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- 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.

+ References

No definition available.

+ Details

Name:	us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of vesting of share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

Name:	us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=casy_CertainOfficersandKeyEmployeeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PlanNameAxis=casy_StockIncentivePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=casy_NonEmployeeMembersOfTheBoardMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_TitleOfIndividualAxis=us-gaap_ChiefExecutiveOfficerMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=us-gaap_ShareBasedCompensationAwardTrancheThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=casy_SharebasedCompensationAwardTrancheFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VestingAxis=casy_SharebasedCompensationAwardTrancheFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Preferred and Common Stock- Schedule of Restricted Stock and Restricted Stock Units Granted (Details) - USD ($) $ in Thousands							12 Months Ended
	Apr. 12, 2016	Jun. 05, 2015	Sep. 19, 2014	Jun. 06, 2014	Sep. 13, 2013	Jun. 19, 2013	Apr. 30, 2016	Apr. 30, 2015	Apr. 30, 2014
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted							114,200	91,000	91,650
Officers & Key employees \| 2009 Stock Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted		104,200		91,000		77,650
Fair Value at Grant Date		$ 9,135		$ 6,584		$ 4,816
Officers & Key employees \| 2009 Stock Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted		48,913		30,538
Fair Value at Grant Date		$ 4,288		$ 2,209
Non-employee board members \| 2009 Stock Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted					14,000
Fair Value at Grant Date					$ 958
Non-employee board members \| 2009 Stock Incentive Plan \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted			13,955
Fair Value at Grant Date			$ 990
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Shares Granted	10,000
Fair Value at Grant Date	$ 1,060
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units \| Awards to Vest May 1, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage	20.00%
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units \| Awards to Vest May 1, 2018
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage	20.00%
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units \| Awards to Vest May 1, 2019
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage	20.00%
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units \| Awards to Vest May 1, 2020
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage	20.00%
CEO \| 2009 Stock Incentive Plan \| Restricted Stock Units \| Awards to Vest May 1, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Vesting percentage	20.00%