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Inventories - Summary Of Inventories (Detail) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016
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Inventory Disclosure [Abstract] |  |
Crude oil and refinery feedstocks | $ 2,148 | $ 2,208
Refined products | 2,674 | 2,810
Materials and supplies | 414 | 485
Merchandise | 156 | 153
Total | $ 5,392 | $ 5,656

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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://www.xbrl.org/2003/role/presentationRef -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 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/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 35 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=68049868&loc=d3e3927-108312 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765 + 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/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Inventory -URI http://asc.fasb.org/extlink&oid=6516093 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)(5)) -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://www.xbrl.org/2003/role/presentationRef -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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