Condensed Consolidated Statement Of Comprehensive Income - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Condensed Consolidated Statement Of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 4,783	$ 4,090
Other comprehensive income (net of income taxes)
Foreign exchange translation adjustment	(804)	1,408
Adjustment for foreign exchange translation (gain)/loss included in net income	168
Postretirement benefits reserves adjustment (excluding amortization)	(434)	(25)
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	237	256
Total other comprehensive income	(833)	1,639
Comprehensive income including noncontrolling interests	3,950	5,729
Comprehensive income attributable to noncontrolling interests	(9)	159
Comprehensive income attributable to ExxonMobil	$ 3,959	$ 5,570

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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Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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