Mineral Leaseholds, Net (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Summary of minerals leaseholds, net of accumulated depletion [Abstract]
Mineral leaseholds	$ 1,335		$ 1,333
Less: accumulated depletion	(540)		(530)
Mineral leaseholds, net	795		$ 803
Depletion expense	$ 10	$ 2

The noncash expense charged against earnings to recognize the consumption of natural resources.

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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.

+ References

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Mineral properties, net of adjustments.

+ References

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