Condensed Consolidated Statement Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Condensed Consolidated Statement Of Comprehensive Income [Abstract]
Net income (loss) including noncontrolling interests	$ (1,169)	$ 3,391	$ (1,939)	$ 5,797
Other comprehensive income (loss) (net of income taxes)
Foreign exchange translation adjustment	2,875	600	(2,774)	1,349
Postretirement benefits reserves adjustment (excluding amortization)	(136)	(34)	(49)	(60)
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	203	141	407	326
Total other comprehensive income (loss)	2,942	707	(2,416)	1,615
Comprehensive income (loss) including noncontrolling interests	1,773	4,098	(4,355)	7,412
Comprehensive income (loss) attributable to noncontrolling interests	131	391	(541)	573
Comprehensive income (loss) attributable to ExxonMobil	$ 1,642	$ 3,707	$ (3,814)	$ 6,839

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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