Inventories (Tables)	12 Months Ended
Dec. 31, 2019
Inventories [Abstract]
Inventories	Note 4—Inventories Inventories at December 31 were: Millions of Dollars 2019 2018 Crude oil and natural gas $ 472 432 Materials and supplies 554 575 $ 1,026 1,007

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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