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Inventories - Additional Information (Details) - USD ($) | 12 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2019
Inventory Disclosure [Abstract] |  |  |
Impact of liquidations of previously established LIFO layers on net income | $ 9,500,000 | $ 0 | $ 0
Impact of liquidations of previously established LIFO layers on diluted earnings per share | $ 0.14 |  |

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- Definition Effect of LIFO inventory liquidation on earnings per share diluted. + References No definition available. + Details
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- Definition The effect of liquidating LIFO (last in first out) inventory layers on income. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SAB Topic 11.F) -URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100079-122729 + Details
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- References No definition available. + Details
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