Inventories (Tables)	3 Months Ended
Mar. 31, 2020
Inventories [Abstract]
Inventories	Note 3—Inventories Inventories consisted of the following: Millions of Dollars March 31 December 31 2020 2019 Crude oil and natural gas $ 192 472 Materials and supplies 534 554 $ 726 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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