Condensed Consolidated Statement Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Condensed Consolidated Statement Of Comprehensive Income [Abstract]
Net income (loss) including noncontrolling interests	$ (770)	$ 2,406
Other comprehensive income (loss) (net of income taxes)
Foreign exchange translation adjustment	(5,649)	749
Postretirement benefits reserves adjustment (excluding amortization)	87	(26)
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	204	185
Total other comprehensive income (loss)	(5,358)	908
Comprehensive income (loss) including noncontrolling interests	(6,128)	3,314
Comprehensive income (loss) attributable to noncontrolling interests	(672)	182
Comprehensive income (loss) attributable to ExxonMobil	$ (5,456)	$ 3,132

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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