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Inventories (Summary of Inventories) (Details) - USD ($) $ in Millions | Mar. 31, 2026 | Dec. 31, 2025
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Inventory Disclosure [Abstract] |  |
Crude oil and other feedstocks | $ 3,360 | $ 3,272
Refined products | 6,035 | 5,350
Materials and supplies | 1,369 | 1,507
Total | $ 10,764 | $ 10,129

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- Definition Balance includes refined products. Inventories are carried at the lower of cost or market value. The cost of inventories of refined products is determined primarily under the last-in, first-out ("LIFO") method. + References No definition available. + Details
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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://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481372/852-10-55-10 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483467/210-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(a)(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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