Income Taxes (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 31, 2022	Dec. 02, 2019	Dec. 31, 2018
Income Taxes [Abstract]
Interest and penalties (benefiting) charging earnings		$ 1	$ 4	$ 3
Undistributed Earnings Of Foreign Subsidiaries	$ 4,384	4,384
Unrecognized Tax Benefits That Would Impact Effective Tax Rate	1,261	1,261	1,128	1,100
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	47	47	46	42
Income Taxes Information [Line Items]
Net deferred tax assets	4,588	4,588	4,666	151
Deferred income taxes	6,179	6,179	3,747
U.S. foreign tax credits	5,500	5,500				$ 6,642
Estimated tax payable on undistributed unremitted foreign income		219
Unrecognized tax benefit	1,345	1,345	1,206	1,177			$ 1,081
Income tax provision (benefit)		4,633	(485)	2,267
Increase (decrease) in valuation allowance	6,642
Disposition CVE Common Shares [Member]
Income Taxes Information [Line Items]
Increase (decrease) in valuation allowance		218
Impairment Of APLNG Investment [Member]
Income Taxes Information [Line Items]
Increase (decrease) in valuation allowance		206
Disposition Of Indonesia Entities [Member]
Income Taxes Information [Line Items]
U.S. foreign tax credits	29	29
Sale Of Two U.K. Subsidiaries [Member]
Income Taxes Information [Line Items]
Gain on disposition				1,700
Income tax provision (benefit)				335
Capital loss tax benefit				2,100
U.S. income tax benefit				285
Sale Of Two U.K. Subsidiaries [Member] | Malaysia Block G [Member]
Income Taxes Information [Line Items]
Income tax provision (benefit)				$ 164
Subsequent Event [Member]
Income Taxes Information [Line Items]
Unrecognized tax benefit					$ 475
Certain Jurisdictions Outside Of Domestic [Member]
Income Taxes Information [Line Items]
Operating loss carryforwards	1,900	1,900
Australia West [Member]
Income Taxes Information [Line Items]
Reversal of deferred tax assets			92
Gain on disposition			587
Income tax provision (benefit)			(10)
Capital loss tax benefit			313
Increase (decrease) in valuation allowance			178
Concho Resources Incorporated [Member]
Income Taxes Information [Line Items]
Reversal of deferred tax assets		(1,100)
Noncurrent Assets [Member]
Income Taxes Information [Line Items]
Net deferred tax assets	$ 340	$ 340	$ 363