Inventories - Components of Inventory (Detail) - USD ($) $ in Thousands	Dec. 31, 2021	Sep. 30, 2021
Inventory Disclosure [Abstract]
Product	$ 53,801	$ 37,890
Parts and equipment	23,934	23,293
Total inventory	$ 77,735	$ 61,183

Carrying amount as of the balance sheet date of petroleum or crude oil.

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Gross amount of components of assembled products that can be sold directly or indirectly through sales of assembled products.

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-Name Accounting Standards Codification
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