Inventories (Tables)	3 Months Ended
Mar. 31, 2021
Inventories [Abstract]
Inventories	Note 2—Inventories Inventories consisted of the following: Millions of Dollars March 31 December 31 2021 2020 Crude oil and natural gas $ 541 461 Materials and supplies 557 541 $ 1,098 1,002

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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