Inventories - Schedule of Inventories (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Inventory Disclosure [Abstract]
Crude oil	$ 791	$ 799
Other raw materials and unfinished products	662	656
Finished products	1,421	1,329
Lower of cost or market reserve	(386)	(289)
Crude oil and refined products	2,488	2,495
Process chemicals	46	43
Repair and maintenance supplies and other	249	260
Materials, supplies and other	295	303
Total inventories	$ 2,783	$ 2,798

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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

+ References

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-Topic 852
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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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Amount of valuation reserve for inventory.

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The aggregate carrying amount as of the balance sheet date of items held by the entity which are partially completed at the time of measurement and unprocessed items that will go through the production process and become part of the final product. Includes supplies used directly or indirectly in the manufacturing or production process. This element may be used when the reporting entity combines work in process and raw materials into an aggregate amount.

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

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Gross amount of components used by the entity which are bought from another entity rather than produced by the entity.

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Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer.

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