PROPERTY, PLANT AND EQUIPMENT (Book Value of Land and Mineral Rights Disclosure) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Mineral rights:
Mineral Properties, Gross	$ 773	$ 537
Mineral Properties, Accumulated Depletion	(142)	(134)
Mineral Properties, Net	631	403
Land Rights	$ 361	$ 12

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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The accumulated decrease in the carrying value of the mineral properties as a result of mine or mineral production.

+ References

No definition available.

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Carrying amount at the balance sheet date of mineral properties, gross of adjustments.

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Mineral properties, net of adjustments.

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