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Inventories - Summary Of Inventories (Detail) - USD ($) $ in Millions | Sep. 30, 2019 | Dec. 31, 2018
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Inventory Disclosure [Abstract] |  |
Crude oil and refinery feedstocks | $ 3,415 | $ 3,655
Refined products | 5,152 | 5,234
Materials and supplies | 907 | 720
Merchandise | 222 | 228
Total | $ 9,696 | $ 9,837

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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 The aggregate carrying amount as of the balance sheet date of unrefined petroleum and the liquid hydrocarbon components recovered from natural gas. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount as of the balance sheet date of merchandise inventory purchased by a retailer, wholesaler or distributor and held for future sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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