Disclosures About Segments And Related Information (Schedule of Geographic Sales And Operating Revenue) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	$ 45,425	$ 63,422	$ 132,836	$ 192,559
U.S. [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	15,851	22,711	46,162	67,370
Non-U.S. [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	29,574	40,711	86,674	125,189
Canada [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	3,566	4,945	9,537	15,141
United Kingdom [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	2,827	4,042	8,424	13,244
Singapore [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	2,400	2,942	6,883	9,197
France [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	2,273	3,266	6,446	9,597
Italy [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	2,055	2,691	5,241	7,830
Belgium [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	$ 1,504	$ 2,598	$ 4,639	$ 9,371