Condensed Consolidated Statement Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss) including noncontrolling interests	$ (709)	$ 3,247	$ (2,648)	$ 9,044
Other comprehensive income (loss) (net of income taxes)
Foreign exchange translation adjustment	1,469	(1,424)	(1,305)	(75)
Adjustment for foreign exchange translation (gain)/loss included in net income	14	0	14	0
Postretirement benefits reserves adjustment (excluding amortization)	(140)	103	(189)	43
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	206	186	613	512
Total other comprehensive income (loss)	1,549	(1,135)	(867)	480
Comprehensive income (loss) including noncontrolling interests	840	2,112	(3,515)	9,524
Comprehensive income (loss) attributable to noncontrolling interests	92	14	(449)	587
Comprehensive income (loss) attributable to ExxonMobil	$ 748	$ 2,098	$ (3,066)	$ 8,937

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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