Consolidated Statement Of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Consolidated Statement Of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$ 47,681	$ 42,206	$ 31,398
Other comprehensive income (net of income taxes)
Foreign exchange translation adjustment	920	(867)	1,034
Adjustment for foreign exchange translation (gain)/loss included in net income	(4,352)		25
Postretirement benefits reserves adjustment (excluding amortization)	(3,574)	(4,907)	(1,161)
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	2,395	1,217	1,040
Change in fair value of cash flow hedges		28	184
Realized (gain)/ loss from settled cash flow hedges included in net income		(83)	(129)
Total other comprehensive income	(4,611)	(4,612)	993
Comprehensive income including noncontrolling interests	43,070	37,594	32,391
Comprehensive income attributable to noncontrolling interests	1,251	834	1,293
Comprehensive income attributable to ExxonMobil	$ 41,819	$ 36,760	$ 31,098