Non-Mineral Leases - End Notes (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Net	$ 42,269,000,000	$ 45,698,000,000
Co Venturer Member
Short-term Lease Commitment, Amount	31,000,000
Short Term Lease Commitment Lease Not Commenced	18,000,000
Property plant equipment \| Co Venturer Member
Property, Plant and Equipment, Net	335,000,000
Finance Lease, Liability, Current	$ 56,000,000
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	Debt, Current
Finance Lease, Liability, Noncurrent	$ 579,000,000
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Long-term Debt and Capital Lease Obligations

Amount of short term lease commitment related to leases which have not yet commenced.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
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Indicates line item in statement of financial position that includes current finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent.

+ References

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Indicates line item in statement of financial position that includes noncurrent finance lease liability.

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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-SubTopic 10
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Amount of short-term lease commitment.

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