Note 1 - Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Apr. 30, 2014	Apr. 30, 2013	Apr. 30, 2012
Note 1 - Significant Accounting Policies (Details) [Line Items]
Number of Stores	1,808
Number of States in which Entity Operates	14
Population Of Communities	5,000
Excess of Replacement or Current Costs over Stated LIFO Value	$ 48,777	$ 44,792
Goodwill	120,406	114,791
Asset Impairment Charges	2,542	3,680	226
Excise Taxes Collected	646,000	596,000	527,000
Asset Retirement Obligation in Other Assets Net of Amortization	8,391	8,011
Asset Retirement Obligation, Liabilities Incurred	12,854	12,176
Self Insurance Reserve	$ 28,429	$ 24,039
Number of Operating Segments	1
Number of Reportable Segments	1
Gasoline [Member] \| Sales Revenue, Goods, Net [Member]
Note 1 - Significant Accounting Policies (Details) [Line Items]
Concentration Risk, Percentage	71.00%
Grocery and Other Merchandise [Member] \| Sales Revenue, Goods, Net [Member]
Note 1 - Significant Accounting Policies (Details) [Line Items]
Concentration Risk, Percentage	20.00%
Prepared Food and Fountain [Member] \| Sales Revenue, Goods, Net [Member]
Note 1 - Significant Accounting Policies (Details) [Line Items]
Concentration Risk, Percentage	9.00%

The recorded asset for asset retirement obligations is recorded in other assets,net of amortization.

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Population of Communities

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of asset retirement obligations incurred during the period.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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The excess of replacement or current cost over the stated LIFO (last in first out) inventory value when the LIFO inventory method is utilized.

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The excise taxes collected by a public utility and reported in revenues if the amount of excise taxes is equal to 1 percent or more of such total.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The number of states the entity operates in as of the balance sheet date.

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Represents the number of stores.

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Carrying amount (including both current and noncurrent portions) of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property.

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