Cash Flow Information (Cash Payments For Interest And Income Taxes) (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
InterOil Corporation [Member]
Total purchase price			$ 2,700
Bass Family Permian Basin Resources [Member]
Total purchase price			6,200
InterOil Corporation Permian Basin And Other Assets [Member]
Consideration transferred equity interests issued and issuable			$ 7,800
Equity interests issued or issuable, number of shares			96
Maturity greater than three months [Member]
Net cash flow from issuance/(repayment) of commercial paper	$ 4,600	$ 275	$ (121)
Proceeds from issuance of commercial paper	18,900	4,000	3,600
Repayments of commercial paper	$ 14,300	$ 3,800	$ 3,700

Number of shares of equity interests issued or issuable to acquire entity.

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