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Significant Accounting Policies (Details) $ in Thousands |  | 12 Months Ended
--- | --- | ---
May 13, 2021 USD ($) | Apr. 30, 2024 USD ($) segment merchandise_category store people state | Apr. 30, 2023 USD ($) | Apr. 30, 2022 USD ($)
Accounting Policies [Abstract] |  |  |  |
Number of stores | store |  | 2,658 |  |
Number of states in which entity operates | state |  | 17 |  |
Population of communities (many less than) | people |  | 20,000 |  |
Concentration Risk |  |  |  |
Excess of current cost over the stated LIFO Value |  | $ 151,461 | $ 138,962 |
Amortization |  | 14,108 | 12,302 | $ 9,449
Goodwill |  | 652,663 | 615,342 |
Asset impairment charges |  | 4,057 | 3,500 | $ 1,056
Contract liability |  | 52,934 | 55,561 |
Discounted liability of asset retirement obligation |  | 39,954 | 36,978 |
Self insurance reserve |  | 57,369 | 61,168 |
Accrued environmental liability |  | $ 299 | 268 |
Number of operating segments | segment |  | 1 |  |
Number of reportable segments | segment |  | 1 |  |
Number of merchandise categories | merchandise_category |  | 3 |  |
Buchanan Energy |  |  |  |
Concentration Risk |  |  |  |
Intangible assets acquired | $ 31,100 |  |  |
Gift Cards |  |  |  |
Concentration Risk |  |  |  |
Contract liability |  | $ 17,985 | 17,463 |
Capitalized software costs |  |  |  |
Concentration Risk |  |  |  |
Finite-lived intangible assets |  | $ 37,619 | 42,495 |
Capitalized software costs | Minimum |  |  |  |
Concentration Risk |  |  |  |
Intangible asset useful life |  | 2 years |  |
Capitalized software costs | Maximum |  |  |  |
Concentration Risk |  |  |  |
Intangible asset useful life |  | 13 years |  |
Customer Relationships |  |  |  |
Concentration Risk |  |  |  |
Intangible assets, net |  | $ 24,880 | 26,953 |
Accumulated amortization |  | 6,220 | $ 4,147 |
Annual amortization, year one |  | 2,073 |  |
Annual amortization, year two |  | 2,073 |  |
Annual amortization, year three |  | 2,073 |  |
Annual amortization, year four |  | 2,073 |  |
Annual amortization, year five |  | $ 2,073 |  |
Customer Relationships | Buchanan Energy |  |  |  |
Concentration Risk |  |  |  |
Useful life | 15 years |  |  |

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