Consolidated Statement Of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash flows from operating activities
Net income including noncontrolling interests	$ 42,206	$ 31,398	$ 19,658
Adjustments for noncash transactions
Depreciation and depletion	15,583	14,760	11,917
Deferred income tax charges/(credits)	142	(1,135)
Postretirement benefits expense in excess of/(less than) net payments	544	1,700	(1,722)
Other long-term obligation provisions in excess of/(less than) payments	(151)	160	731
Dividends received greater than/(less than) equity in current earnings of equity companies	(273)	(596)	(483)
Changes in operational working capital, excluding cash and debt
Reduction/(increase) - Notes and accounts receivable	(7,906)	(5,863)	(3,170)
- Inventories	(2,208)	(1,148)	459
- Other current assets	222	913	132
Increase/(reduction) - Accounts and other payables	8,880	9,943	1,420
Net (gain) on asset sales	(2,842)	(1,401)	(488)
All other items - net	1,148	(318)	(16)
Net cash provided by operating activities	55,345	48,413	28,438
Cash flows from investing activities
Additions to property, plant and equipment	(30,975)	(26,871)	(22,491)
Proceeds associated with sales of subsidiaries, property, plant and equipment, and sales and returns of investments	11,133	3,261	1,545
Decrease/(increase) in restricted cash and cash equivalents	224	(628)
Additional investments and advances	(3,586)	(1,239)	(2,752)
Collection of advances	1,119	1,133	724
Additions to marketable securities	(1,754)	(15)	(16)
Sales of marketable securities	1,674	155	571
Net cash used in investing activities	(22,165)	(24,204)	(22,419)
Cash flows from financing activities
Additions to long-term debt	702	1,143	225
Reductions in long-term debt	(266)	(6,224)	(68)
Additions to short-term debt	1,063	598	1,336
Reductions in short-term debt	(1,103)	(2,436)	(1,575)
Additions/(reductions) in debt with three months or less maturity	1,561	709	(71)
Cash dividends to ExxonMobil shareholders	(9,020)	(8,498)	(8,023)
Cash dividends to noncontrolling interests	(306)	(281)	(280)
Changes in noncontrolling interests	(16)	(7)	(113)
Tax benefits related to stock-based awards	260	122	237
Common stock acquired	(22,055)	(13,093)	(19,703)
Common stock sold	924	1,043	752
Net cash used in financing activities	(28,256)	(26,924)	(27,283)
Effects of exchange rate changes on cash	(85)	(153)	520
Increase/(decrease) in cash and cash equivalents	4,839	(2,868)	(20,744)
Cash and cash equivalents at beginning of year	7,825	10,693	31,437
Cash and cash equivalents at end of year	$ 12,664	$ 7,825	$ 10,693

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).