Inventories (Tables)	9 Months Ended
Sep. 30, 2020
Inventories [Abstract]
Inventories	Note 3—Inventories Inventories consisted of the following: Millions of Dollars September 30 December 31 2020 2019 Crude oil and natural gas $ 503 472 Materials and supplies 531 554 $ 1,034 1,026

Tabular disclosure of the carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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