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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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Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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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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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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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

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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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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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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
Significant Accounting Policies (Details) $ in Thousands	Apr. 30, 2019 USD ($) people state segment store merchandise_category	Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)	May 01, 2018 USD ($)	Apr. 30, 2016 USD ($)
Accounting Policies [Abstract]
Number of stores \| store	2,146
Number of states in which entity operates \| state	16
Population of communities (many less than) \| people	5,000
Concentration Risk
Shareholders' equity	$ 1,408,769	$ 1,271,141	$ 1,190,620		$ 1,083,463
Deferred income taxes	385,788	341,946
Excess of current cost over the stated LIFO Value	80,814	73,494
Goodwill	157,223	140,258
Asset impairment charges	1,167	507	705
Recorded asset retirement obligation (net of amortization)	11,793	11,280
Discounted liability of asset retirement obligation	18,058	17,087
Self insurance reserve	$ 44,334	39,777
Number of operating segments \| segment	1
Number of reportable segments \| segment	1
Number of merchandise categories \| merchandise_category	3
Fuel
Concentration Risk
Excise taxes collected	$ 988,000	$ 919,000	$ 866,000
Fuel \| Retail Sales
Concentration Risk
Concentration risk percentage	63.00%
Grocery & other merchandise \| Retail Sales
Concentration Risk
Concentration risk percentage	26.00%
Prepared food & fountain \| Retail Sales
Concentration Risk
Concentration risk percentage	11.00%
Accounting Standards Update 2014-09 \| GIft Cards
Concentration Risk
Shareholders' equity				$ 879
Deferred income taxes				321
Accounting Standards Update 2014-09 \| Box Tops
Concentration Risk
Shareholders' equity				(5,019)
Deferred income taxes				$ (1,816)