Non-Mineral Leases - Balance Sheet (Details) - USD ($)	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Property Plant And Equipment Gross	$ 97,746,000,000		$ 110,597,000,000
Accumulated depreciation, depletion and amortization	55,477,000,000		64,899,000,000
Property, Plant and Equipment, Net	42,269,000,000		45,698,000,000
Short-term debt	105,000,000		112,000,000
Long-term debt	14,790,000,000		14,856,000,000
Finance Lease, Liability Total	720,000,000
Prepaid expenses and other current assets	2,259,000,000		575,000,000
Other assets (leases)	2,426,000,000		1,344,000,000
Other Liabilities, Current	2,045,000,000		1,259,000,000
Operating Lease, Liability	932,000,000
Previously Reported [Member]
Property Plant And Equipment Gross			1,044,000,000
Accumulated depreciation, depletion and amortization			550,000,000
Property, Plant and Equipment, Net			494,000,000
Short-term debt			79,000,000
Long-term debt			698,000,000
Finance Lease, Liability Total			$ 777,000,000
Accounting Standards Update 2016-02 [Member]
Property Plant And Equipment Gross	1,039,000,000
Accumulated depreciation, depletion and amortization	649,000,000
Property, Plant and Equipment, Net	390,000,000
Prepaid expenses and other current assets	40,000,000
Other assets (leases)	$ 896,000,000
Accounting Standards Update 2016-02 [Member] \| Restatement Adjustment [Member]
Operating Lease, Right-of-Use Asset		$ 998,000,000
Operating Lease, Liability, Current		$ 998,000,000

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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