Summary Of Significant Accounting Policies (Schedule Of Inventories) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
LIFO inventories
FIFO value	$ 0	$ 1,022
LIFO valuation reserve	0	(91)
LIFO inventories carrying value	0	931
FIFO inventories	3,310	3,106
Market inventories	7,941	4,704
Supplies and other inventories	462	429
Total inventories	$ 11,713	$ 9,170

The FIFO value of inventories accounted using LIFO method.

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The value of inventories measured at market value.

+ References

No definition available.

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- Definition

The amount of FIFO (first in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

+ References

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Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of products used directly or indirectly in the manufacturing or production process, which may or may not become part of the final product. May also include items used in the storage, presentation or transportation of physical goods.

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The amount of LIFO (last in first out) inventory present at the reporting date when inventory is also valued using different valuation methods.

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