Inventories

9 Months Ended

Sep. 30, 2020

Inventory Disclosure [Abstract]

Inventories

Inventories

    Crude oil and natural gas are recorded at weighted average cost and carried at the lower of cost or net realizable value. Supplies and other items consist principally of tubular goods and equipment which are valued at weighted average cost and reviewed periodically for obsolescence or impairment when market conditions indicate. The continued volatility and future decline in crude oil and natural gas prices could affect the value of our inventories and result in future impairments.

(In millions)	September 30, 2020		December 31, 2019
Crude oil and natural gas	$	11	$	10
Supplies and other items	66		62
Inventories	$	77	$	72