Exxon Mobil (XOM) 10-K 25 Feb 15 2014 FY Annual report Financial data

Document_And_Entity_Informatio

Document And Entity Information (USD $)	12 Months Ended
In Billions, except Share data, unless otherwise specified	Dec. 31, 2014	Jan. 31, 2015	Jun. 30, 2014
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	FALSE
Document Period End Date	31-Dec-14
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2014
Trading Symbol	XOM
Entity Registrant Name	EXXON MOBIL CORP
Entity Central Index Key	34088
Current Fiscal Year End Date	-19
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		4,194,690,266
Entity Public Float			$429

Consolidated_Statement_Of_Inco

Consolidated Statement Of Income (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Revenues and other income
Sales and other operating revenue	$394,105	[1],[2]	$420,836	[1],[2]	$451,509	[1],[2]
Income from equity affiliates	13,323		13,927		15,010
Other income	4,511		3,492		14,162
Total revenues and other income	411,939		438,255		480,681
Costs and other deductions
Crude oil and product purchases	225,972		244,156		263,535
Production and manufacturing expenses	40,859		40,525		38,521
Selling, general and administrative expenses	12,598		12,877		13,877
Depreciation and depletion	17,297		17,182		15,888
Exploration expenses, including dry holes	1,669		1,976		1,840
Interest expense	286		9		327
Sales-based taxes	29,342	[1]	30,589	[1]	32,409	[1]
Other taxes and duties	32,286		33,230		35,558
Total costs and other deductions	360,309		380,544		401,955
Income before income taxes	51,630		57,711		78,726
Income taxes	18,015		24,263		31,045
Net income including noncontrolling interests	33,615		33,448		47,681
Net income attributable to noncontrolling interests	1,095		868		2,801
Net income attributable to ExxonMobil	$32,520		$32,580		$44,880
Earnings per common share (dollars)	$7.60	[3]	$7.37	[3]	$9.70	[3]
Earnings per common share - assuming dilution (dollars)	$7.60		$7.37		$9.70
[1]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012.
[2]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
[3]	The earnings per common share and earnings per common share - assuming dilution are the same in each period shown.

Consolidated_Statement_Of_Inco1

Consolidated Statement Of Income (Parenthetical) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Consolidated Statement Of Income [Abstract]
Sales-based taxes included in sales and other operating revenue	$29,342	[1]	$30,589	[1]	$32,409	[1]
[1]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012.

Consolidated_Statement_Of_Comp

Consolidated Statement Of Comprehensive Income (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Consolidated Statement Of Comprehensive Income [Abstract]
Net income including noncontrolling interests	$33,615	$33,448	$47,681
Other comprehensive income (net of income taxes)
Foreign exchange translation adjustment	-5,847	-3,620	920
Adjustment for foreign exchange translation (gain)/loss included in net income	152	-23	-4,352
Postretirement benefits reserves adjustment (excluding amortization)	-4,262	3,174	-3,574
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	1,111	1,820	2,395
Unrealized change in fair value of stock investments	-63
Realized (gain)/ loss from stock investments included in net income	3
Total other comprehensive income	-8,906	1,351	-4,611
Comprehensive income including noncontrolling interests	24,709	34,799	43,070
Comprehensive income attributable to noncontrolling interests	421	760	1,251
Comprehensive income attributable to ExxonMobil	$24,288	$34,039	$41,819

Consolidated_Balance_Sheet

Consolidated Balance Sheet (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current assets
Cash and cash equivalents	$4,616	$4,644
Cash and cash equivalents - restricted	42	269
Notes and accounts receivable, less estimated doubtful amounts	28,009	33,152
Inventories
Crude oil, products and merchandise	12,384	12,117
Materials and supplies	4,294	4,018
Other current assets	3,565	5,108
Total current assets	52,910	59,308
Investments, advances and long-term receivables	35,239	36,328
Property, plant and equipment, at cost, less accumulated depreciation and depletion	252,668	243,650
Other assets, including intangibles, net	8,676	7,522
Total assets	349,493	346,808
Current liabilities
Notes and loans payable	17,468	15,808
Accounts payable and accrued liabilities	42,227	48,085
Income taxes payable	4,938	7,831
Total current liabilities	64,633	71,724
Long-term debt	11,653	6,891
Postretirement benefits reserves	25,802	20,646
Deferred income tax liabilities	39,230	40,530
Long-term obligations to equity companies	5,325	4,742
Other long-term obligations	21,786	21,780
Total liabilities	168,429	166,313
Commitments and contingencies (Note 16)
Equity
Common stock without par value (9,000 million shares authorized, 8,019 million shares issued)	10,792	10,077
Earnings reinvested	408,384	387,432
Accumulated other comprehensive income	-18,957	-10,725
Common stock held in treasury (3,818 million shares in 2014 and 3,684 million shares in 2013)	-225,820	-212,781
ExxonMobil share of equity	174,399	174,003
Noncontrolling interests	6,665	6,492
Total equity	181,064	180,495
Total liabilities and equity	$349,493	$346,808

Consolidated_Balance_Sheet_Par

Consolidated Balance Sheet (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Consolidated Balance Sheet [Abstract]
Common stock, without par value
Common stock, shares authorized	9,000,000,000	9,000,000,000
Common stock, shares issued	8,019,000,000	8,019,000,000
Common stock held in treasury, shares	3,818,000,000	3,684,000,000

Consolidated_Statement_Of_Cash

Consolidated Statement Of Cash Flows (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities
Net income including noncontrolling interests	$33,615	$33,448	$47,681
Adjustments for noncash transactions
Depreciation and depletion	17,297	17,182	15,888
Deferred income tax charges/(credits)	1,540	754	3,142
Postretirement benefits expense in excess of/(less than) net payments	524	2,291	-315
Other long-term obligation provisions in excess of/(less than) payments	1,404	-2,566	1,643
Dividends received greater than/(less than) equity in current earnings of equity companies	-358	3	-1,157
Changes in operational working capital, excluding cash and debt
Reduction/(increase) - Notes and accounts receivable	3,118	-305	-1,082
Reduction/(increase) - Inventories	-1,343	-1,812	-1,873
Reduction/(increase) - Other current assets	-68	-105	-42
Increase/(reduction) - Accounts and other payables	-6,639	-2,498	3,624
Net (gain) on asset sales	-3,151	-1,828	-13,018
All other items - net	-823	350	1,679
Net cash provided by operating activities	45,116	44,914	56,170
Cash flows from investing activities
Additions to property, plant and equipment	-32,952	-33,669	-34,271
Proceeds associated with sales of subsidiaries, property, plant and equipment, and sales and returns of investments	4,035	2,707	7,655
Decrease/(increase) in restricted cash and cash equivalents	227	72	63
Additional investments and advances	-1,631	-4,435	-598
Collection of advances	3,346	1,124	1,550
Net cash used in investing activities	-26,975	-34,201	-25,601
Cash flows from financing activities
Additions to long-term debt	5,731	345	995
Reductions in long-term debt	-69	-13	-147
Additions to short-term debt		16	958
Reductions in short-term debt	-745	-756	-4,488
Additions/(reductions) in debt with three months or less maturity	2,049	12,012	-226
Cash dividends to ExxonMobil shareholders	-11,568	-10,875	-10,092
Cash dividends to noncontrolling interests	-248	-304	-327
Changes in noncontrolling interests		-1	204
Tax benefits related to stock-based awards	115	48	130
Common stock acquired	-13,183	-15,998	-21,068
Common stock sold	30	50	193
Net cash used in financing activities	-17,888	-15,476	-33,868
Effects of exchange rate changes on cash	-281	-175	217
Increase/(decrease) in cash and cash equivalents	-28	-4,938	-3,082
Cash and cash equivalents at beginning of year	4,644	9,582	12,664
Cash and cash equivalents at end of year	$4,616	$4,644	$9,582

Consolidated_Statement_Of_Chan

Consolidated Statement Of Changes In Equity (USD $)	Total	ExxonMobil Share Of Common Stock [Member]	ExxonMobil Share Of Earnings Reinvested [Member]	ExxonMobil Share Of Accumulated Other Comprehensive Income [Member]	ExxonMobil Share Of Common Stock Held In Treasury [Member]	ExxonMobil Share Of Equity [Member]	Noncontrolling Interests [Member]	Common Stock Outstanding [Member]
In Millions, except Share data	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)	USD ($)
Balance at Dec. 31, 2011	$160,744	$9,512	$330,939	($9,123)	($176,932)	$154,396	$6,348
Balance (in shares) - outstanding at Dec. 31, 2011								4,734,000,000
Balance (in shares) - in treasury at Dec. 31, 2011					-3,285,000,000
Balance (in shares) - issued at Dec. 31, 2011		8,019,000,000
Amortization of stock-based awards	806	806				806
Tax benefits related to stock-based awards	178	178				178
Other	-2,284	-843				-843	-1,441
Net income for the year	47,681		44,880			44,880	2,801
Dividends - common shares (company)			-10,092			-10,092
Dividends - common shares (NCI)							-327
Dividends - common shares (total)	-10,419
Other comprehensive income	-4,611			-3,061		-3,061	-1,550
Acquisitions, at cost (company)					-21,068	-21,068
Acquisitions, at cost (NCI)							-34
Acquisitions, at cost (total)	-21,102
Dispositions	667				667	667
Acquisitions (in shares)					-244,000,000			-244,000,000
Dispositions (in shares)					12,000,000			12,000,000
Balance at Dec. 31, 2012	171,660	9,653	365,727	-12,184	-197,333	165,863	5,797
Balance (in shares) - outstanding at Dec. 31, 2012								4,502,000,000
Balance (in shares) - in treasury at Dec. 31, 2012					-3,517,000,000
Balance (in shares) - issued at Dec. 31, 2012		8,019,000,000
Amortization of stock-based awards	761	761				761
Tax benefits related to stock-based awards	162	162				162
Other	-259	-499				-499	240
Net income for the year	33,448		32,580			32,580	868
Dividends - common shares (company)			-10,875			-10,875
Dividends - common shares (NCI)							-304
Dividends - common shares (total)	-11,179
Other comprehensive income	1,351			1,459		1,459	-108
Acquisitions, at cost (company)					-15,998	-15,998
Acquisitions, at cost (NCI)							-1
Acquisitions, at cost (total)	-15,999
Dispositions	550				550	550
Acquisitions (in shares)					-177,000,000			-177,000,000
Dispositions (in shares)					10,000,000			10,000,000
Balance at Dec. 31, 2013	180,495	10,077	387,432	-10,725	-212,781	174,003	6,492
Balance (in shares) - outstanding at Dec. 31, 2013								4,335,000,000
Balance (in shares) - in treasury at Dec. 31, 2013	3,684,000,000				-3,684,000,000
Balance (in shares) - issued at Dec. 31, 2013	8,019,000,000	8,019,000,000
Amortization of stock-based awards	780	780				780
Tax benefits related to stock-based awards	49	49				49
Other	-114	-114				-114
Net income for the year	33,615		32,520			32,520	1,095
Dividends - common shares (company)			-11,568			-11,568
Dividends - common shares (NCI)							-248
Dividends - common shares (total)	-11,816
Other comprehensive income	-8,906			-8,232		-8,232	-674
Acquisitions, at cost (company)					-13,183	-13,183
Acquisitions, at cost (total)	-13,183
Dispositions	144				144	144
Acquisitions (in shares)					-136,000,000			-136,000,000
Dispositions (in shares)					2,000,000			2,000,000
Balance at Dec. 31, 2014	$181,064	$10,792	$408,384	($18,957)	($225,820)	$174,399	$6,665
Balance (in shares) - outstanding at Dec. 31, 2014								4,201,000,000
Balance (in shares) - in treasury at Dec. 31, 2014	3,818,000,000				-3,818,000,000
Balance (in shares) - issued at Dec. 31, 2014	8,019,000,000	8,019,000,000

Summary_Of_Accounting_Policies

Summary Of Accounting Policies	12 Months Ended
	Dec. 31, 2014
Summary Of Accounting Policies [Abstract]
Summary Of Accounting Policies	1. Summary of Accounting Policies
	Principles of Consolidation. The Consolidated Financial Statements include the accounts of subsidiaries the Corporation controls. They also include the Corporation’s share of the undivided interest in certain upstream assets, liabilities, revenues and expenses.
	Amounts representing the Corporation’s interest in entities that it does not control, but over which it exercises significant influence, are included in “Investments, advances and long-term receivables.” The Corporation’s share of the net income of these companies is included in the Consolidated Statement of Income caption “Income from equity affiliates.”
	Majority ownership is normally the indicator of control that is the basis on which subsidiaries are consolidated. However, certain factors may indicate that a majority-owned investment is not controlled and therefore should be accounted for using the equity method of accounting. These factors occur where the minority shareholders are granted by law or by contract substantive participating rights. These include the right to approve operating policies, expense budgets, financing and investment plans, and management compensation and succession plans.
	The Corporation’s share of the cumulative foreign exchange translation adjustment for equity method investments is reported in Accumulated Other Comprehensive Income.
	Evidence of loss in value that might indicate impairment of investments in companies accounted for on the equity method is assessed to determine if such evidence represents a loss in value of the Corporation’s investment that is other than temporary. Examples of key indicators include a history of operating losses, negative earnings and cash flow outlook, significant downward revisions to oil and gas reserves, and the financial condition and prospects for the investee’s business segment or geographic region. If evidence of an other than temporary loss in fair value below carrying amount is determined, an impairment is recognized. In the absence of market prices for the investment, discounted cash flows are used to assess fair value.
	Revenue Recognition. The Corporation generally sells crude oil, natural gas and petroleum and chemical products under short-term agreements at prevailing market prices. In some cases (e.g., natural gas), products may be sold under long-term agreements, with periodic price adjustments. Revenues are recognized when the products are delivered, which occurs when the customer has taken title and has assumed the risks and rewards of ownership, prices are fixed or determinable and collectibility is reasonably assured.
	Revenues from the production of natural gas properties in which the Corporation has an interest with other producers are recognized on the basis of the Corporation’s net working interest. Differences between actual production and net working interest volumes are not significant.
	Purchases and sales of inventory with the same counterparty that are entered into in contemplation of one another are combined and recorded as exchanges measured at the book value of the item sold.
	Sales-Based Taxes. The Corporation reports sales, excise and value-added taxes on sales transactions on a gross basis in the Consolidated Statement of Income (included in both revenues and costs).
	Derivative Instruments. The Corporation makes limited use of derivative instruments. The Corporation does not engage in speculative derivative activities or derivative trading activities, nor does it use derivatives with leveraged features. When the Corporation does enter into derivative transactions, it is to offset exposures associated with interest rates, foreign currency exchange rates and hydrocarbon prices that arise from existing assets, liabilities and forecasted transactions.
	The gains and losses resulting from changes in the fair value of derivatives are recorded in income. In some cases, the Corporation designates derivatives as fair value hedges, in which case the gains and losses are offset in income by the gains and losses arising from changes in the fair value of the underlying hedged item.
	Fair Value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Hierarchy Levels 1, 2 and 3 are terms for the priority of inputs to valuation techniques used to measure fair value. Hierarchy Level 1 inputs are quoted prices in active markets for identical assets or liabilities. Hierarchy Level 2 inputs are inputs other than quoted prices included within Level 1 that are directly or indirectly observable for the asset or liability. Hierarchy Level 3 inputs are inputs that are not observable in the market.
	Inventories. Crude oil, products and merchandise inventories are carried at the lower of current market value or cost (generally determined under the last-in, first-out method – LIFO). Inventory costs include expenditures and other charges (including depreciation) directly and indirectly incurred in bringing the inventory to its existing condition and location. Selling expenses and general and administrative expenses are reported as period costs and excluded from inventory cost. Inventories of materials and supplies are valued at cost or less.
	Property, Plant and Equipment. Depreciation, depletion and amortization, based on cost less estimated salvage value of the asset, are primarily determined under either the unit-of-production method or the straight-line method, which is based on estimated asset service life taking obsolescence into consideration. Maintenance and repairs, including planned major maintenance, are expensed as incurred. Major renewals and improvements are capitalized and the assets replaced are retired.
	The Corporation uses the “successful efforts” method to account for its exploration and production activities. Under this method, costs are accumulated on a field-by-field basis. Costs incurred to purchase, lease, or otherwise acquire a property (whether unproved or proved) are capitalized when incurred. Exploratory well costs are carried as an asset when the well has found a sufficient quantity of reserves to justify its completion as a producing well and where the Corporation is making sufficient progress assessing the reserves and the economic and operating viability of the project. Exploratory well costs not meeting these criteria are charged to expense. Other exploratory expenditures, including geophysical costs and annual lease rentals, are expensed as incurred. Development costs including costs of productive wells and development dry holes are capitalized.
	Acquisition costs of proved properties are amortized using a unit-of-production method, computed on the basis of total proved oil and gas reserves. Capitalized exploratory drilling and development costs associated with productive depletable extractive properties are amortized using unit-of-production rates based on the amount of proved developed reserves of oil, gas and other minerals that are estimated to be recoverable from existing facilities using current operating methods. Under the unit-of-production method, oil and gas volumes are considered produced once they have been measured through meters at custody transfer or sales transaction points at the outlet valve on the lease or field storage tank.
	Production involves lifting the oil and gas to the surface and gathering, treating, field processing and field storage of the oil and gas. The production function normally terminates at the outlet valve on the lease or field production storage tank. Production costs are those incurred to operate and maintain the Corporation’s wells and related equipment and facilities and are expensed as incurred. They become part of the cost of oil and gas produced. These costs, sometimes referred to as lifting costs, include such items as labor costs to operate the wells and related equipment; repair and maintenance costs on the wells and equipment; materials, supplies and energy costs required to operate the wells and related equipment; and administrative expenses related to the production activity.
	Proved oil and gas properties held and used by the Corporation are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. Assets are grouped at the lowest level for which there are identifiable cash flows that are largely independent of the cash flows of other groups of assets.
	The Corporation estimates the future undiscounted cash flows of the affected properties to judge the recoverability of carrying amounts. Cash flows used in impairment evaluations are developed using annually updated corporate plan investment evaluation assumptions for crude oil and natural gas commodity prices, refining and chemical margins and foreign currency exchange rates. Annual volumes are based on field production profiles, which are also updated annually. Prices for other petroleum and chemical products are based on corporate plan assumptions developed annually by major region and also for investment evaluation purposes. Cash flow estimates for impairment testing exclude derivative instruments.
	Impairment analyses are generally based on proved reserves. Where probable reserves exist, an appropriately risk-adjusted amount of these reserves may be included in the impairment evaluation. An asset group would be impaired if the undiscounted cash flows were less than its carrying value. Impairments are measured by the amount the carrying value exceeds fair value.
	Significant unproved properties are assessed for impairment individually, and valuation allowances against the capitalized costs are recorded based on the estimated economic chance of success and the length of time that the Corporation expects to hold the properties. Properties that are not individually significant are aggregated by groups and amortized based on development risk and average holding period. The valuation allowances are reviewed at least annually.
	Gains on sales of proved and unproved properties are only recognized when there is neither uncertainty about the recovery of costs applicable to any interest retained nor any substantial obligation for future performance by the Corporation.
	Losses on properties sold are recognized when incurred or when the properties are held for sale and the fair value of the properties is less than the carrying value.
	Interest costs incurred to finance expenditures during the construction phase of multiyear projects are capitalized as part of the historical cost of acquiring the constructed assets. The project construction phase commences with the development of the detailed engineering design and ends when the constructed assets are ready for their intended use. Capitalized interest costs are included in property, plant and equipment and are depreciated over the service life of the related assets.
	Asset Retirement Obligations and Environmental Liabilities. The Corporation incurs retirement obligations for certain assets. The fair values of these obligations are recorded as liabilities on a discounted basis, which is typically at the time the assets are installed. The costs associated with these liabilities are capitalized as part of the related assets and depreciated. Over time, the liabilities are accreted for the change in their present value.
	Liabilities for environmental costs are recorded when it is probable that obligations have been incurred and the amounts can be reasonably estimated. These liabilities are not reduced by possible recoveries from third parties and projected cash expenditures are not discounted.
	Foreign Currency Translation. The Corporation selects the functional reporting currency for its international subsidiaries based on the currency of the primary economic environment in which each subsidiary operates.
	Downstream and Chemical operations primarily use the local currency. However, the U.S. dollar is used in countries with a history of high inflation (primarily in Latin America) and Singapore, which predominantly sells into the U.S. dollar export market. Upstream operations which are relatively self-contained and integrated within a particular country, such as Canada, the United Kingdom, Norway and continental Europe, use the local currency. Some Upstream operations, primarily in Asia and Africa, use the U.S. dollar because they predominantly sell crude and natural gas production into U.S. dollar-denominated markets.
	For all operations, gains or losses from remeasuring foreign currency transactions into the functional currency are included in income.
	Stock-Based Payments. The Corporation awards stock-based compensation to employees in the form of restricted stock and restricted stock units. Compensation expense is measured by the price of the stock at the date of grant and is recognized in income over the requisite service period.

Accounting_Changes

Accounting Changes	12 Months Ended
	Dec. 31, 2014
Accounting Changes [Abstract]
Accounting Changes	2. Accounting Changes
	The Corporation did not adopt authoritative guidance in 2014 that had a material impact on the Corporation’s financial statements.
	In May 2014, the Financial Accounting Standards Board issued a new standard, Revenue from Contracts with Customers. The standard establishes a single revenue recognition model for all contracts with customers, eliminates industry specific requirements, and expands disclosure requirements. The standard is required to be adopted beginning January 1, 2017. ExxonMobil is evaluating the standard and its effect on the Corporation’s financial statements.

Miscellaneous_Financial_Inform

Miscellaneous Financial Information	12 Months Ended
	Dec. 31, 2014
Miscellaneous Financial Information [Abstract]
Miscellaneous Financial Information	3. Miscellaneous Financial Information
	Research and development expenses totaled $971 million in 2014, $1,044 million in 2013 and $1,042 million in 2012.
	Net income included before-tax aggregate foreign exchange transaction losses of $225 million, and gains of $155 million and $159 million in 2014, 2013 and 2012, respectively.
	In 2014, 2013 and 2012, net income included gains of $187 million, $282 million and $328 million, respectively, attributable to the combined effects of LIFO inventory accumulations and drawdowns. The aggregate replacement cost of inventories was estimated to exceed their LIFO carrying values by $10.6 billion and $21.2 billion at December 31, 2014, and 2013, respectively.
	Crude oil, products and merchandise as of year-end 2014 and 2013 consist of the following:
			2014	2013
			(billions of dollars)
	Petroleum products		4.1	3.9
	Crude oil		4.6	4.7
	Chemical products		2.9	2.9
	Gas/other		0.8	0.6
		Total	12.4	12.1

Other_Comprehensive_Income_Inf

Other Comprehensive Income Information	12 Months Ended
	Dec. 31, 2014
Other Comprehensive Income Information [Abstract]
Other Comprehensive Income Information	4. Other Comprehensive Income Information
			Cumulative			Post-
			Foreign			retirement			Unrealized
			Exchange			Benefits			Change in
	ExxonMobil Share of Accumulated Other		Translation			Reserves			Stock
	Comprehensive Income		Adjustment			Adjustment			Investments	Total
			(millions of dollars)
	Balance as of December 31, 2011		4,168			-13,291			-	-9,123
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	842			-3,402			-	-2,560
	Amounts reclassified from accumulated other
		comprehensive income	-2,600			2,099			-	-501
	Total change in accumulated other comprehensive income		-1,758			-1,303			-	-3,061
	Balance as of December 31, 2012		2,410			-14,594			-	-12,184
	Balance as of December 31, 2012		2,410			-14,594			-	-12,184
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	-3,233			2,963			-	-270
	Amounts reclassified from accumulated other
		comprehensive income	-23			1,752			-	1,729
	Total change in accumulated other comprehensive income		-3,256			4,715			-	1,459
	Balance as of December 31, 2013		-846			-9,879			-	-10,725
	Balance as of December 31, 2013		-846			-9,879			-	-10,725
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	-5,258			-4,132			-63	-9,453
	Amounts reclassified from accumulated other
		comprehensive income	152			1,066			3	1,221
	Total change in accumulated other comprehensive income		-5,106			-3,066			-60	-8,232
	Balance as of December 31, 2014		-5,952			-12,945			-60	-18,957
	Amounts Reclassified Out of Accumulated Other
	Comprehensive Income - Before-tax Income/(Expense)			2014		2013		2012
				(millions of dollars)
	Foreign exchange translation gain/(loss) included in net income
		(Statement of Income line: Other income)		-152		23		4,352
	Amortization and settlement of postretirement benefits reserves
		adjustment included in net periodic benefit costs (1)		-1,571		-2,616		-3,621
	Realized change in fair value of stock investments included in net income
		(Statement of Income line: Other income)		-5		-		-
	(1) These accumulated other comprehensive income components are included in the computation of net periodic pension cost. (See Note 17 – Pension and Other Postretirement Benefits for additional details.)
	Income Tax (Expense)/Credit For
	Components of Other Comprehensive Income		2014		2013		2012
			(millions of dollars)
	Foreign exchange translation adjustment		292		218		-236
	Postretirement benefits reserves adjustment (excluding amortization)		2,009		-1,540		1,619
	Amortization and settlement of postretirement benefits reserves
		adjustment included in net periodic benefit costs	-460		-796		-1,226
	Unrealized change in fair value of stock investments		34		-		-
	Realized change in fair value of stock investments included in net income		-2		-		-
	Total		1,873		-2,118		157

Cash_Flow_Information

Cash Flow Information	12 Months Ended
	Dec. 31, 2014
Cash Flow Information [Abstract]
Cash Flow Information	5. Cash Flow Information
	The Consolidated Statement of Cash Flows provides information about changes in cash and cash equivalents. Highly liquid investments with maturities of three months or less when acquired are classified as cash equivalents.
	For 2014, the “Net (gain) on asset sales” on the Consolidated Statement of Cash Flows includes before-tax gains from the sale of Hong Kong power operations, additional proceeds related to the 2013 sale of a partial interest in Iraq, the sale of Downstream affiliates in the Caribbean and the sale or exchange of Upstream properties in the U.S., Canada, and Malaysia. For 2013, the amount includes before-tax gains from the sale of a partial interest in Iraq, the sale of Downstream affiliates in the Caribbean and the sale of service stations. For 2012, the amount includes before-tax gains related to the Japan restructuring, the sale of an Upstream property in Angola, exchanges of Upstream properties, the sale of U.S. service stations and the sale of Downstream affiliates in Malaysia and Switzerland. These gains are reported in “Other income” on the Consolidated Statement of Income.
	In 2014, ExxonMobil completed asset exchanges, primarily non-cash transactions, of approximately $1.2 billion. This amount is not included in the “Sales of subsidiaries, investments, and property, plant and equipment” or the “Additions to property, plant and equipment” lines on the Statement of Cash Flows.
	In 2012, the Corporation’s interest in a cost company was redeemed. As part of the redemption, a variable note due in 2035 issued by Mobil Services (Bahamas) Ltd. was assigned to a consolidated ExxonMobil affiliate. This note is no longer classified as third party long-term debt. This assignment did not result in a “Reduction in long-term debt” on the Statement of Cash Flows.
	In 2012, ExxonMobil completed asset exchanges, primarily noncash transactions, of approximately $1 billion. This amount is not included in the “Sales of subsidiaries, investments, and property, plant and equipment” or the “Additions to property, plant and equipment” lines on the Statement of Cash Flows.
		2014	2013	2012
		(millions of dollars)
	Cash payments for interest	380	426	555
	Cash payments for income taxes	18,085	25,066	24,349

Additional_Working_Capital_Inf

Additional Working Capital Information	12 Months Ended
	Dec. 31, 2014
Additional Working Capital Information [Abstract]
Additional Working Capital Information	6. Additional Working Capital Information
				Dec. 31	Dec. 31
				2014	2013
				(millions of dollars)
	Notes and accounts receivable
		Trade, less reserves of $113 million and $112 million		18,541	25,993
		Other, less reserves of $48 million and $28 million		9,468	7,159
			Total	28,009	33,152
	Notes and loans payable
		Bank loans		473	723
		Commercial paper		16,225	14,051
		Long-term debt due within one year		770	1,034
			Total	17,468	15,808
	Accounts payable and accrued liabilities
		Trade payables		25,286	30,920
		Payables to equity companies		6,589	6,587
		Accrued taxes other than income taxes		3,290	3,883
		Other		7,062	6,695
			Total	42,227	48,085
	The Corporation has short-term committed lines of credit of $6.3 billion which were unused as of December 31, 2014. These lines are available for general corporate purposes.
	The weighted-average interest rate on short-term borrowings outstanding was 0.3 percent and 0.4 percent at December 31, 2014, and 2013, respectively.

Equity_Company_Information

Equity Company Information	12 Months Ended
	Dec. 31, 2014
Equity Company Information [Abstract]
Equity Company Information	7. Equity Company Information
	The summarized financial information below includes amounts related to certain less-than-majority-owned companies and majority-owned subsidiaries where minority shareholders possess the right to participate in significant management decisions (see Note 1). These companies are primarily engaged in oil and gas exploration and production, natural gas marketing, and refining operations in North America; natural gas exploration, production and distribution, and downstream operations in Europe; and exploration, production, liquefied natural gas (LNG) operations, refining operations, petrochemical manufacturing, and fuel sales in Asia. Also included are several refining, petrochemical manufacturing, and marketing ventures.
	The Corporation’s ownership in these ventures is in the form of shares in corporate joint ventures as well as interests in partnerships. Differences between the company’s carrying value of an equity investment and its underlying equity in the net assets of the affiliate are assigned to the extent practicable to specific assets and liabilities based on the company’s analysis of the factors giving rise to the difference. The amortization of this difference, as appropriate, is included in “income from equity affiliates.”
	The share of total equity company revenues from sales to ExxonMobil consolidated companies was 14 percent, 13 percent and 16 percent in the years 2014, 2013 and 2012, respectively.
	In 2013 and 2014, the Corporation and Rosneft established various entities to conduct exploration and research activities. Periods of disproportionate funding will result in the Corporation recognizing, during the early phases of the projects, an investment that is larger than its equity share in these entities. These joint ventures are considered Variable Interest Entities. However, since the Corporation is not the primary beneficiary of these entities, the joint ventures are reported as equity companies. In 2014, the European Union and United States imposed sanctions relating to the Russian energy sector. In compliance with the sanctions and all general and specific licenses, prohibited activities involving offshore Russia in the Black Sea, Arctic regions, and onshore western Siberia have been wound down. The Corporation's maximum exposure to loss from these joint ventures as of December 31, 2014, is $1.0 billion.
				2014			2013			2012
	Equity Company				ExxonMobil			ExxonMobil			ExxonMobil
	Financial Summary			Total		Share	Total		Share	Total		Share
				(millions of dollars)
	Total revenues			183,708		55,855	236,161		68,084	224,953		67,572
	Income before income taxes			65,549		19,014	69,454		19,999	69,411		20,882
	Income taxes			20,520		5,684	21,618		6,069	20,703		5,868
		Income from equity affiliates		45,029		13,330	47,836		13,930	48,708		15,014
	Current assets			49,905		16,802	62,398		19,545	59,612		18,483
	Long-term assets			110,754		33,619	116,450		35,695	111,131		33,798
		Total assets		160,659		50,421	178,848		55,240	170,743		52,281
	Current liabilities			37,333		11,472	54,550		15,243	49,698		14,265
	Long-term liabilities			66,231		19,470	68,857		20,873	68,855		19,715
		Net assets		57,095		19,479	55,441		19,124	52,190		18,301
	A list of significant equity companies as of December 31, 2014, together with the Corporation’s percentage ownership interest, is detailed below:
			Percentage
			Ownership
			Interest
		Upstream
		Aera Energy LLC	48
		BEB Erdgas und Erdoel GmbH & Co. KG	50
		Cameroon Oil Transportation Company S.A.	41
		Cross Timbers Energy, LLC	50
		Golden Pass LNG Terminal LLC	18
		Karmorneftegaz Holding SARL	33
		Marine Well Containment Company LLC	10
		Nederlandse Aardolie Maatschappij B.V.	50
		Qatar Liquefied Gas Company Limited	10
		Qatar Liquefied Gas Company Limited (2)	24
		Ras Laffan Liquefied Natural Gas Company Limited	25
		Ras Laffan Liquefied Natural Gas Company Limited (II)	31
		Ras Laffan Liquefied Natural Gas Company Limited (3)	30
		South Hook LNG Terminal Company Limited	24
		Tengizchevroil, LLP	25
		Terminale GNL Adriatico S.r.l.	71
		Downstream
		Chalmette Refining, LLC	50
		Fujian Refining & Petrochemical Co. Ltd.	25
		Saudi Aramco Mobil Refinery Company Ltd.	50
		Chemical
		Al-Jubail Petrochemical Company	50
		Infineum Holdings B.V.	50
		Infineum USA L.P.	50
		Saudi Yanbu Petrochemical Co.	50

Investments_Advances_And_LongT

Investments, Advances And Long-Term Receivables	12 Months Ended
	Dec. 31, 2014
Investments, Advances And Long-Term Receivables [Abstract]
Investments, Advances And Long-Term Receivables	8. Investments, Advances and Long-Term Receivables
				Dec. 31,	Dec. 31,
				2014	2013
				(millions of dollars)
	Companies carried at equity in underlying assets
		Investments		20,017	19,619
		Advances		9,818	10,476
			Total equity company investments and advances	29,835	30,095
	Companies carried at cost or less and stock investments carried at fair value			526	115
	Long-term receivables and miscellaneous investments at cost or less, net of reserves
		of $2,662 million and $2,938 million		4,878	6,118
			Total	35,239	36,328

Property_Plant_And_Equipment_A

Property, Plant And Equipment And Asset Retirement Obligations	12 Months Ended
	Dec. 31, 2014
Property, Plant And Equipment And Asset Retirement Obligations [Abstract]
Property, Plant And Equipment And Asset Retirement Obligations	9. Property, Plant and Equipment and Asset Retirement Obligations
			31-Dec-14		31-Dec-13
	Property, Plant and Equipment		Cost	Net	Cost	Net
			(millions of dollars)
	Upstream		347,170	205,308	336,359	197,554
	Downstream		53,327	22,639	54,456	23,219
	Chemical		30,717	14,918	29,487	13,965
	Other		15,575	9,803	14,215	8,912
		Total	446,789	252,668	434,517	243,650
	In the Upstream segment, depreciation is generally on a unit-of-production basis, so depreciable life will vary by field. In the Downstream segment, investments in refinery and lubes basestock manufacturing facilities are generally depreciated on a straight-line basis over a 25-year life and service station buildings and fixed improvements over a 20-year life. In the Chemical segment, investments in process equipment are generally depreciated on a straight-line basis over a 20-year life.
	Accumulated depreciation and depletion totaled $194,121 million at the end of 2014 and $190,867 million at the end of 2013. Interest capitalized in 2014, 2013 and 2012 was $344 million, $309 million and $506 million, respectively.
	Asset Retirement Obligations
	The Corporation incurs retirement obligations for certain assets. The fair values of these obligations are recorded as liabilities on a discounted basis, which is typically at the time the assets are installed. In the estimation of fair value, the Corporation uses assumptions and judgments regarding such factors as the existence of a legal obligation for an asset retirement obligation; technical assessments of the assets; estimated amounts and timing of settlements; discount rates; and inflation rates. Asset retirement obligations incurred in the current period were Level 3 fair value measurements. The costs associated with these liabilities are capitalized as part of the related assets and depreciated as the reserves are produced. Over time, the liabilities are accreted for the change in their present value.
	Asset retirement obligations for downstream and chemical facilities generally become firm at the time the facilities are permanently shut down and dismantled. These obligations may include the costs of asset disposal and additional soil remediation. However, these sites have indeterminate lives based on plans for continued operations and as such, the fair value of the conditional legal obligations cannot be measured, since it is impossible to estimate the future settlement dates of such obligations.
	The following table summarizes the activity in the liability for asset retirement obligations:
			2014	2013
			(millions of dollars)
	Beginning balance		12,988	11,973
		Accretion expense and other provisions	871	785
		Reduction due to property sales	-151	-97
		Payments made	-724	-664
		Liabilities incurred	122	603
		Foreign currency translation	-908	-344
		Revisions	1,226	732
	Ending balance		13,424	12,988

Accounting_For_Suspended_Explo

Accounting For Suspended Exploratory Well Costs	12 Months Ended
	Dec. 31, 2014
Accounting For Suspended Exploratory Well Costs [Abstract]
Accounting For Suspended Exploratory Well Costs	10. Accounting for Suspended Exploratory Well Costs
	The Corporation continues capitalization of exploratory well costs when the well has found a sufficient quantity of reserves to justify its completion as a producing well and the Corporation is making sufficient progress assessing the reserves and the economic and operating viability of the project. The term “project” as used in this report can refer to a variety of different activities and does not necessarily have the same meaning as in any government payment transparency reports.
	The following two tables provide details of the changes in the balance of suspended exploratory well costs as well as an aging summary of those costs.
	Change in capitalized suspended exploratory well costs:
				2014		2013	2012
				(millions of dollars)
	Balance beginning at January 1			2,707		2,679	2,881
		Additions pending the determination of proved reserves		1,095		293	868
		Charged to expense		-28		-52	-95
		Reclassifications to wells, facilities and equipment based on the
			determination of proved reserves	-160		-107	-631
		Divestments/Other		-27		-106	-344
	Ending balance at December 31			3,587		2,707	2,679
	Ending balance attributed to equity companies included above			645		13	3
	Period end capitalized suspended exploratory well costs:
				2014		2013	2012
				(millions of dollars)
	Capitalized for a period of one year or less			1,095		293	866
		Capitalized for a period of between one and five years		1,659		1,705	1,176
		Capitalized for a period of between five and ten years		544		470	401
		Capitalized for a period of greater than ten years		289		239	236
	Capitalized for a period greater than one year - subtotal			2,492		2,414	1,813
			Total	3,587		2,707	2,679
	Exploration activity often involves drilling multiple wells, over a number of years, to fully evaluate a project. The table below provides a numerical breakdown of the number of projects with suspended exploratory well costs which had their first capitalized well drilled in the preceding 12 months and those that have had exploratory well costs capitalized for a period greater than 12 months.
				2014		2013	2012
	Number of projects with first capitalized well drilled in the preceding 12 months			8		8	10
	Number of projects that have exploratory well costs capitalized for a period
		of greater than 12 months		53		50	45
			Total	61		58	55
	Of the 53 projects that have exploratory well costs capitalized for a period greater than 12 months as of December 31, 2014, 15 projects have drilling in the preceding 12 months or exploratory activity planned in the next two years, while the remaining 38 projects are those with completed exploratory activity progressing toward development. The table below provides additional detail for those 38 projects, which total $1,035 million.
				Years
			Dec. 31,	Wells
	Country/Project		2014	Drilled	Comment
		(millions of dollars)
	Angola
	- Kaombo Split Hub Phase 2		20	2005 - 2006	Evaluating development plan to tie into planned production facilities.
	- Perpetua-Zinia-Acacia		15	2008 - 2009	Oil field near Pazflor development, awaiting capacity in existing/planned infrastructure.
	Australia
	- East Pilchard		8	2001	Gas field near Kipper/Tuna development, awaiting capacity in existing/planned
					infrastructure.
	- SE Longtom		12	2010	Gas field near Tuna development, awaiting capacity in existing/planned infrastructure.
	- SE Remora		38	2010	Gas field near Marlin development, awaiting capacity in existing/planned infrastructure.
	Indonesia
	- Alas Tua West		16	2010	Evaluating development plan to tie into planned production facilities.
	- Cepu Gas		28	2008 - 2011	Development activity under way, while continuing commercial discussions with the
					government.
	- Kedung Keris		11	2011	Evaluating development plan to tie into planned production facilities.
	- Natuna		118	1981 - 1983	Development activity under way, while continuing discussions with the government
					on contract terms pursuant to executed Heads of Agreement.
	Kazakhstan
	- Kairan		53	2004 - 2007	Evaluating commercialization and field development alternatives, while continuing
					discussions with the government regarding the development plan.
	Malaysia
	- Besar		18	1992 - 2010	Gas field off the east coast of Malaysia; progressing development plan.
	- Bindu		2	1995	Awaiting capacity in existing/planned infrastructure.
	Nigeria
	- Bolia		15	2002 - 2006	Evaluating development plan, while continuing discussions with the government
					regarding regional hub strategy.
	- Bosi		79	2002 - 2006	Development activity under way, while continuing discussions with the government
					regarding development plan.
	- Bosi Central		16	2006	Development activity under way, while continuing discussions with the government
					regarding development plan.
	- Erha Northeast		26	2008	Evaluating development plan for tieback to existing production facilities.
	- Owowo		50	2009 - 2012	Continuing discussions with the government regarding contract terms.
- Pegi		32	2009	Awaiting capacity in existing/planned infrastructure.
- Satellite Field		12	2013	Evaluating development plan to tie into planned production facilities.
Development Phase 2
- Other (4 projects)		14	2002	Evaluating and pursuing development of several additional discoveries.
Norway
- Gamma		15	2008 - 2009	Evaluating development plan for tieback to existing production facilities.
- Lavrans		18	1995 - 1999	Evaluating development plan, awaiting capacity in existing Kristin production facility.
- Other (7 projects)		29	2008 - 2013	Evaluating development plans, including potential for tieback to existing production
				facilities.
Papua New Guinea
- Juha		28	2007	Progressing development plans to tie into existing LNG facilities.
- P'nyang		58	2012	Evaluating development alternatives to tie into existing/planned infrastructure.
Republic of Congo
- Mer Tres Profonde Sud		56	2000 - 2007	Evaluating development alternatives, while continuing discussions with the government
				regarding development plan.
United Kingdom
- Phyllis		8	2004	Evaluating development plan for tieback to existing production facilities.
United States
- Hadrian North		209	2010 - 2013	Evaluating development plan to tie into existing production facilities.
- Tip Top		31	2009	Evaluating development concept and requisite facility upgrades.
Total 2014 (38 projects)		1,035

Leased_Facilities

Leased Facilities	12 Months Ended
	Dec. 31, 2014
Leased Facilities [Abstract]
Leased Facilities	11. Leased Facilities
	At December 31, 2014, the Corporation and its consolidated subsidiaries held noncancelable operating charters and leases covering drilling equipment, tankers, service stations and other properties with minimum undiscounted lease commitments totaling $6,213 million as indicated in the table. Estimated related rental income from noncancelable subleases is $70 million.
						Related
				Lease Payments		Sublease
				Under Minimum		Rental
				Commitments		Income
				(millions of dollars)
		2015		2,034		31
		2016		1,379		7
		2017		774		6
		2018		418		3
		2019		312		3
		2020 and beyond		1,296		20
		Total		6,213		70
	Net rental cost under both cancelable and noncancelable operating leases incurred during 2014, 2013 and 2012 were as follows:
			2014	2013	2012
			(millions of dollars)
	Rental cost		4,077	3,841	3,851
	Less sublease rental income		52	44	44
	Net rental cost		4,025	3,797	3,807

Earnings_Per_Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share	12. Earnings Per Share
		2014	2013	2012
	Earnings per common share
	Net income attributable to ExxonMobil (millions of dollars)	32,520	32,580	44,880
	Weighted average number of common shares outstanding (millions of shares)	4,282	4,419	4,628
	Earnings per common share (dollars) (1)	7.6	7.37	9.7
	Dividends paid per common share (dollars)	2.7	2.46	2.18
	(1) The earnings per common share and earnings per common share - assuming dilution are the same in each period shown.

Financial_Instruments_And_Deri

Financial Instruments And Derivatives	12 Months Ended
	Dec. 31, 2014
Financial Instruments And Derivatives [Abstract]
Financial Instruments And Derivatives	13. Financial Instruments and Derivatives
	Financial Instruments. The fair value of financial instruments is determined by reference to observable market data and other valuation techniques as appropriate. The only category of financial instruments where the difference between fair value and recorded book value is notable is long-term debt. The estimated fair value of total long-term debt, excluding capitalized lease obligations, was $11.7 billion and $6.8 billion at December 31, 2014, and 2013, respectively, as compared to recorded book values of $11.3 billion and $6.5 billion at December 31, 2014, and 2013, respectively. The increase in the estimated fair value and book value of long-term debt reflects the Corporation’s issuance of $5,500 million of long-term debt in the first quarter of 2014.
	The fair value of long-term debt by hierarchy level at December 31, 2014, is: Level 1 $11,036 million; Level 2 $561 million; and Level 3 $63 million.
	Derivative Instruments. The Corporation’s size, strong capital structure, geographic diversity and the complementary nature of the Upstream, Downstream and Chemical businesses reduce the Corporation’s enterprise-wide risk from changes in interest rates, currency rates and commodity prices. As a result, the Corporation makes limited use of derivatives to mitigate the impact of such changes. The Corporation does not engage in speculative derivative activities or derivative trading activities nor does it use derivatives with leveraged features. When the Corporation does enter into derivative transactions, it is to offset exposures associated with interest rates, foreign currency exchange rates and hydrocarbon prices that arise from existing assets, liabilities and forecasted transactions.
	The estimated fair value of derivative instruments outstanding and recorded on the balance sheet was a net asset of $75 million at year-end 2014 and a net asset of $1 million at year-end 2013. Assets and liabilities associated with derivatives are usually recorded either in “Other current assets” or “Accounts payable and accrued liabilities.”
	The Corporation’s fair value measurement of its derivative instruments use either Level 1 or Level 2 inputs.
	The Corporation recognized a before-tax gain or (loss) related to derivative instruments of $110 million, $(7) million and $(23) million during 2014, 2013 and 2012, respectively. Income statement effects associated with derivatives are usually recorded either in “Sales and other operating revenue” or “Crude oil and product purchases.”
	The Corporation believes there are no material market or credit risks to the Corporation’s financial position, results of operations or liquidity as a result of the derivative activities described above.

LongTerm_Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2014
Long-Term Debt [Abstract]
Long-Term Debt	14. Long-Term Debt
	At December 31, 2014, long-term debt consisted of $11,341 million due in U.S. dollars and $312 million representing the U.S. dollar equivalent at year-end exchange rates of amounts payable in foreign currencies. These amounts exclude that portion of long-term debt, totaling $770 million, which matures within one year and is included in current liabilities. The increase in the book value of long-term debt reflects the Corporation’s issuance of $5,500 million of long-term debt in the first quarter of 2014. The amounts of long-term debt maturing in each of the four years after December 31, 2015, in millions of dollars, are: 2016 – $537; 2017 – $2,993; 2018 – $872; and 2019 – $2,353. At December 31, 2014, the Corporation’s unused long-term credit lines were $0.5 billion.
	Summarized long-term debt at year-end 2014 and 2013 are shown in the table below:
					2014	2013
					(millions of dollars)
		Exxon Mobil Corporation
			0.921% notes due 2017		1,500	-
			Floating-rate notes due 2017 (1)		750	-
			1.819% notes due 2019		1,750	-
			Floating-rate notes due 2019 (2)		500	-
			3.176% notes due 2024		1,000	-
		XTO Energy Inc. (3)
			5.000% senior notes due 2015		-	132
			5.300% senior notes due 2015		-	243
			5.650% senior notes due 2016		207	212
			6.250% senior notes due 2017		477	489
			5.500% senior notes due 2018		383	389
			6.500% senior notes due 2018		474	485
			6.100% senior notes due 2036		199	200
			6.750% senior notes due 2037		309	312
			6.375% senior notes due 2038		236	238
		Mobil Producing Nigeria Unlimited (4)
			Variable notes due 2015-2019		399	742
		Esso (Thailand) Public Company Ltd. (5)
			Variable notes due 2015-2019		121	177
		Mobil Corporation
			8.625% debentures due 2021		249	249
		Industrial revenue bonds due 2015-2051 (6)			2,611	2,527
		Other U.S. dollar obligations (7)			104	112
		Other foreign currency obligations			9	9
		Capitalized lease obligations (8)			375	375
				Total long-term debt	11,653	6,891
	(1) Average effective interest rate of 0.3% in 2014.
	(2) Average effective interest rate of 0.4% in 2014.
	(3) Includes premiums of $219 million in 2014 and $271 million in 2013.
	(4) Average effective interest rate of 4.5% in 2014 and 4.6% in 2013.
	(5) Average effective interest rate of 2.4% in 2014 and 3.3% in 2013.
	(6) Average effective interest rate of 0.03% in 2014 and 0.06% in 2013.
	(7) Average effective interest rate of 4.2% in 2014 and 4.4% in 2013.
	(8) Average imputed interest rate of 7.0% in 2014 and 7.8% in 2013.

Incentive_Program

Incentive Program	12 Months Ended
	Dec. 31, 2014
Incentive Program [Abstract]
Incentive Program	15. Incentive Program
	The 2003 Incentive Program provides for grants of stock options, stock appreciation rights (SARs), restricted stock and other forms of award. Awards may be granted to eligible employees of the Corporation and those affiliates at least 50 percent owned. Outstanding awards are subject to certain forfeiture provisions contained in the program or award instrument. Options and SARs may be granted at prices not less than 100 percent of market value on the date of grant and have a maximum life of 10 years. The maximum number of shares of stock that may be issued under the 2003 Incentive Program is 220 million. Awards that are forfeited, expire or are settled in cash, do not count against this maximum limit. The 2003 Incentive Program does not have a specified term. New awards may be made until the available shares are depleted, unless the Board terminates the plan early. At the end of 2014, remaining shares available for award under the 2003 Incentive Program were 108 million.
	Restricted Stock and Restricted Stock Units. Awards totaling 9,775 thousand, 9,729 thousand, and 10,017 thousand of restricted (nonvested) common stock and restricted (nonvested) common stock units were granted in 2014, 2013 and 2012, respectively. Compensation expense for these awards is based on the price of the stock at the date of grant and is recognized in income over the requisite service period. Shares for these awards are issued to employees from treasury stock. The units that are settled in cash are recorded as liabilities and their changes in fair value are recognized over the vesting period. During the applicable restricted periods, the shares and units may not be sold or transferred and are subject to forfeiture. The majority of the awards have graded vesting periods, with 50 percent of the shares and units in each award vesting after three years and the remaining 50 percent vesting after seven years. Awards granted to a small number of senior executives have vesting periods of five years for 50 percent of the award and of 10 years or retirement, whichever occurs later, for the remaining 50 percent of the award.
	The Corporation has purchased shares in the open market and through negotiated transactions to offset shares issued in conjunction with benefit plans and programs. Purchases may be discontinued at any time without prior notice.
	The following tables summarize information about restricted stock and restricted stock units for the year ended December 31, 2014.
		2014
				Weighted Average
				Grant-Date
	Restricted stock and units outstanding	Shares		Fair Value per Share
		(thousands)		(dollars)
	Issued and outstanding at January 1	45,207			78.29
	2013 award issued in 2014	9,705			94.47
	Vested	-10,286			79.89
	Forfeited	-187			78.89
	Issued and outstanding at December 31	44,439			81.45
	Value of restricted stock and units		2014	2013		2012
	Grant price (dollars)		95.2	94.47		87.24
	Value at date of grant:		(millions of dollars)
	Restricted stock and units settled in stock		858	843		797
	Units settled in cash		73	76		77
	Total value		931	919		874
	As of December 31, 2014, there was $2,339 million of unrecognized compensation cost related to the nonvested restricted awards. This cost is expected to be recognized over a weighted-average period of 4.5 years. The compensation cost charged against income for the restricted stock and restricted stock units was $831 million, $854 million and $854 million for 2014, 2013 and 2012, respectively. The income tax benefit recognized in income related to this compensation expense was $76 million, $78 million and $79 million for the same periods, respectively. The fair value of shares and units vested in 2014, 2013 and 2012 was $946 million, $1,040 million and $926 million, respectively. Cash payments of $73 million, $67 million and $66 million for vested restricted stock units settled in cash were made in 2014, 2013 and 2012, respectively.

Litigation_And_Other_Contingen

Litigation And Other Contingencies	12 Months Ended
	Dec. 31, 2014
Litigation And Other Contingencies [Abstract]
Litigation And Other Contingencies	16. Litigation and Other Contingencies
	Litigation. A variety of claims have been made against ExxonMobil and certain of its consolidated subsidiaries in a number of pending lawsuits. Management has regular litigation reviews, including updates from corporate and outside counsel, to assess the need for accounting recognition or disclosure of these contingencies. The Corporation accrues an undiscounted liability for those contingencies where the incurrence of a loss is probable and the amount can be reasonably estimated. If a range of amounts can be reasonably estimated and no amount within the range is a better estimate than any other amount, then the minimum of the range is accrued. The Corporation does not record liabilities when the likelihood that the liability has been incurred is probable but the amount cannot be reasonably estimated or when the liability is believed to be only reasonably possible or remote. For contingencies where an unfavorable outcome is reasonably possible and which are significant, the Corporation discloses the nature of the contingency and, where feasible, an estimate of the possible loss. For purposes of our contingency disclosures, “significant” includes material matters as well as other matters which management believes should be disclosed. ExxonMobil will continue to defend itself vigorously in these matters. Based on a consideration of all relevant facts and circumstances, the Corporation does not believe the ultimate outcome of any currently pending lawsuit against ExxonMobil will have a material adverse effect upon the Corporation’s operations, financial condition, or financial statements taken as a whole.
	Other Contingencies. The Corporation and certain of its consolidated subsidiaries were contingently liable at December 31, 2014, for guarantees relating to notes, loans and performance under contracts. Where guarantees for environmental remediation and other similar matters do not include a stated cap, the amounts reflect management’s estimate of the maximum potential exposure.
								Dec. 31, 2014
				Equity Company			Other Third-Party
				Obligations (1)			Obligations			Total
							(millions of dollars)
	Guarantees
		Debt-related			3,506			41		3,547
		Other			2,920			3,982		6,902
			Total		6,426			4,023		10,449
	(1) ExxonMobil share.
	The debt-related guarantees shown above include a $3.4 billion completion guarantee provided to lenders in support of the project financing for the Papua New Guinea Liquefied Natural Gas project. On February 4, 2015, the obligations under this guarantee were terminated per the terms of the loan agreement.
	Additionally, the Corporation and its affiliates have numerous long-term sales and purchase commitments in their various business activities, all of which are expected to be fulfilled with no adverse consequences material to the Corporation’s operations or financial condition. Unconditional purchase obligations as defined by accounting standards are those long-term commitments that are noncancelable or cancelable only under certain conditions, and that third parties have used to secure financing for the facilities that will provide the contracted goods or services.
			Payments Due by Period
					2016-	2020 and
			2015		2019	Beyond			Total
			(millions of dollars)
	Unconditional purchase obligations (1)		150		608		337		1,095
	(1) Undiscounted obligations of $1,095 million mainly pertain to pipeline throughput agreements and include $433 million of obligations to equity companies. The present value of these commitments, which excludes imputed interest of $168 million, totaled $927 million.
	In accordance with a nationalization decree issued by Venezuela’s president in February 2007, by May 1, 2007, a subsidiary of the Venezuelan National Oil Company (PdVSA) assumed the operatorship of the Cerro Negro Heavy Oil Project. This Project had been operated and owned by ExxonMobil affiliates holding a 41.67 percent ownership interest in the Project. The decree also required conversion of the Cerro Negro Project into a “mixed enterprise” and an increase in PdVSA’s or one of its affiliate’s ownership interest in the Project, with the stipulation that if ExxonMobil refused to accept the terms for the formation of the mixed enterprise within a specified period of time, the government would “directly assume the activities” carried out by the joint venture. ExxonMobil refused to accede to the terms proffered by the government, and on June 27, 2007, the government expropriated ExxonMobil’s 41.67 percent interest in the Cerro Negro Project.
	On September 6, 2007, affiliates of ExxonMobil filed a Request for Arbitration with the International Centre for Settlement of Investment Disputes (ICSID) invoking ICSID jurisdiction under Venezuela’s Investment Law and the Netherlands-Venezuela Bilateral Investment Treaty. The ICSID Tribunal issued a decision on June 10, 2010, finding that it had jurisdiction to proceed on the basis of the Netherlands-Venezuela Bilateral Investment Treaty. On October 9, 2014, the ICSID Tribunal issued its final award finding in favor of the ExxonMobil affiliates and awarding $1.6 billion as of the date of expropriation, June 27, 2007, and interest from that date at 3.25% compounded annually until the date of payment in full. The Tribunal also noted that one of the Cerro Negro Project agreements provides a mechanism to prevent double recovery between the ICSID award and all or part of an earlier award of $908 million to an ExxonMobil affiliate, Mobil Cerro Negro, Ltd., against PdVSA and a PdVSA affiliate, PdVSA CN, in an arbitration under the rules of the International Chamber of Commerce (ICC). Following the favorable ICSID decision in the fourth quarter of 2014, ExxonMobil recognized earnings of $269 million, net of the remaining asset value, for the proceeds received from the earlier ICC award.
	Judgment was entered on the ICSID award by the United States District Court for the Southern District of New York on October 10, 2014. A motion to vacate that judgment on procedural grounds was filed by the Republic of Venezuela on October 14, 2014, which was denied by the court. Thereafter, the Republic of Venezuela filed a motion to modify the judgment by reducing the rate of interest to be paid on the ICSID award from the entry of the court’s judgment, until the date of payment.
	On October 23, 2014, the Republic of Venezuela filed with ICSID an application to revise the ICSID award such that it requires repayment of the value of the ICC award to PdVSA at the same time as payment is made to the ExxonMobil affiliates for the ICSID award and that provision be made for interest on the amount to be repaid. Thereafter, pursuant to ICSID arbitration rules, the ICSID award was stayed pending further action of the Tribunal. On October 27, 2014, ExxonMobil filed a response with ICSID that contests the application for revision of that award on both factual and jurisdictional grounds. On February 2, 2015, the Republic of Venezuela filed an application to annul the ICSID award. The application alleges that, in issuing the ICSID award, the Tribunal exceeded its powers, failed to state reasons on which the ICSID award was based, and departed from a fundamental rule of procedure. Upon registration of the application with ICSID on February 9, 2015, a further stay of the ICSID award was entered.
	The federal court in New York has stayed its judgment until such time as the stays of the ICSID award entered following the Government of Venezuela’s filing of its two applications have been lifted. The net impact of these matters on the Corporation’s consolidated financial results cannot be reasonably estimated. Regardless, the Corporation does not expect the resolution to have a material effect upon the Corporation’s operations or financial condition.
	An affiliate of ExxonMobil is one of the Contractors under a Production Sharing Contract (PSC) with the Nigerian National Petroleum Corporation (NNPC) covering the Erha block located in the offshore waters of Nigeria. ExxonMobil's affiliate is the operator of the block and owns a 56.25 percent interest under the PSC. The Contractors are in dispute with NNPC regarding NNPC's lifting of crude oil in excess of its entitlement under the terms of the PSC. In accordance with the terms of the PSC, the Contractors initiated arbitration in Abuja, Nigeria, under the Nigerian Arbitration and Conciliation Act. On October 24, 2011, a three-member arbitral Tribunal issued an award upholding the Contractors' position in all material respects and awarding damages to the Contractors jointly in an amount of approximately $1.8 billion plus $234 million in accrued interest. The Contractors petitioned a Nigerian federal court for enforcement of the award, and NNPC petitioned the same court to have the award set aside. On May 22, 2012, the court set aside the award. The Contractors have appealed that judgment. In June 2013, the Contractors filed a lawsuit against NNPC in the Nigerian federal high court in order to preserve their ability to seek enforcement of the PSC in the courts if necessary. In October 2014, the Contractors filed suit in the United States District Court for the Southern District of New York to enforce, if necessary, the arbitration award against NNPC assets residing within that jurisdiction. At this time, the net impact of this matter on the Corporation's consolidated financial results cannot be reasonably estimated. However, regardless of the outcome of enforcement proceedings, the Corporation does not expect the proceedings to have a material effect upon the Corporation's operations or financial condition.

Pension_And_Other_Postretireme

Pension And Other Postretirement Benefits	12 Months Ended
	Dec. 31, 2014
Pension And Other Postretirement Benefits [Abstract]
Pension And Other Postretirement Benefits	17. Pension and Other Postretirement Benefits
	The benefit obligations and plan assets associated with the Corporation’s principal benefit plans are measured on December 31.
				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(percent)
	Weighted-average assumptions used to determine
		benefit obligations at December 31
		Discount rate		4		5		3.1		4.3		4		5
		Long-term rate of compensation increase		5.75		5.75		5.3		5.4		5.75		5.75
				(millions of dollars)
	Change in benefit obligation
		Benefit obligation at January 1		17,304		19,779		27,357		28,670		7,868		9,058
		Service cost		677		801		590		697		140		176
		Interest cost		807		749		1,138		1,076		383		352
		Actuarial loss/(gain)		3,192		-1,520		4,929		-1,454		1,522		-1,267
		Benefits paid (1) (2)		-1,427		-2,520		-1,366		-1,311		-525		-511
		Foreign exchange rate changes		-		-		-2,540		-284		-48		-43
		Amendments, divestments and other		-24		15		-61		-37		96		103
	Benefit obligation at December 31			20,529		17,304		30,047		27,357		9,436		7,868
	Accumulated benefit obligation at December 31			16,385		13,989		26,318		23,949		-		-
	(1) Benefit payments for funded and unfunded plans.
	(2) For 2014 and 2013, other postretirement benefits paid are net of $21 million and $20 million of Medicare subsidy receipts, respectively.
	For selection of the discount rate for U.S. plans, several sources of information are considered, including interest rate market indicators and the discount rate determined by use of a yield curve based on high-quality, noncallable bonds with cash flows that match estimated outflows for benefit payments. For major non-U.S. plans, the discount rate is determined by using bond portfolios with an average maturity approximating that of the liabilities or spot yield curves, both of which are constructed using high-quality, local-currency-denominated bonds.
	The measurement of the accumulated postretirement benefit obligation assumes a health care cost trend rate of 4.5 percent in 2016 and subsequent years. A one-percentage-point increase in the health care cost trend rate would increase service and interest cost by $91 million and the postretirement benefit obligation by $1,070 million. A one-percentage-point decrease in the health care cost trend rate would decrease service and interest cost by $69 million and the postretirement benefit obligation by $844 million.
				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(millions of dollars)
	Change in plan assets
		Fair value at January 1		11,190		12,632		19,283		18,090		620		581
		Actual return on plan assets		1,497		617		3,153		1,604		41		64
		Foreign exchange rate changes		-		-		-1,738		-270		-		-
		Company contribution		1,476		101		554		919		31		35
		Benefits paid (1)		-1,248		-2,171		-912		-869		-224		-60
		Other		-		11		-245		-191		-		-
	Fair value at December 31			12,915		11,190		20,095		19,283		468		620
	(1) Benefit payments for funded plans.
	The funding levels of all qualified pension plans are in compliance with standards set by applicable law or regulation. As shown in the table below, certain smaller U.S. pension plans and a number of non-U.S. pension plans are not funded because local tax conventions and regulatory practices do not encourage funding of these plans. All defined benefit pension obligations, regardless of the funding status of the underlying plans, are fully supported by the financial strength of the Corporation or the respective sponsoring affiliate.
				Pension Benefits
				U.S.				Non-U.S.
				2014		2013		2014		2013
				(millions of dollars)
	Assets in excess of/(less than) benefit obligation
		Balance at December 31
		Funded plans		-4,590		-3,547		-2,113		-941
		Unfunded plans		-3,024		-2,567		-7,839		-7,133
	Total			-7,614		-6,114		-9,952		-8,074
	The authoritative guidance for defined benefit pension and other postretirement plans requires an employer to recognize the overfunded or underfunded status of a defined benefit postretirement plan as an asset or liability in its statement of financial position and to recognize changes in that funded status in the year in which the changes occur through other comprehensive income.
				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(millions of dollars)
	Assets in excess of/(less than) benefit obligation
		Balance at December 31 (1)		-7,614		-6,114		-9,952		-8,074		-8,968		-7,248
	Amounts recorded in the consolidated balance
		sheet consist of:
		Other assets		-		1		302		201		-		-
		Current liabilities		-340		-275		-325		-358		-369		-359
		Postretirement benefits reserves		-7,274		-5,840		-9,929		-7,917		-8,599		-6,889
	Total recorded			-7,614		-6,114		-9,952		-8,074		-8,968		-7,248
	Amounts recorded in accumulated other
		comprehensive income consist of:
		Net actuarial loss/(gain)		6,589		4,780		9,642		7,943		2,997		1,603
	Prior service cost		27		60		429		665		51		65
Total recorded in accumulated other
	comprehensive income		6,616		4,840		10,071		8,608		3,048		1,668
(1) Fair value of assets less benefit obligation shown on the preceding page.
The long-term expected rate of return on funded assets shown below is established for each benefit plan by developing a forward-looking, long-term return assumption for each asset class, taking into account factors such as the expected real return for the specific asset class and inflation. A single, long-term rate of return is then calculated as the weighted average of the target asset allocation percentages and the long-term return assumption for each asset class.
																	Other
					Pension Benefits												Postretirement
					U.S.						Non-U.S.						Benefits
					2014		2013		2012		2014		2013		2012		2014		2013		2012
Weighted-average assumptions used to
	determine net periodic benefit cost for
	years ended December 31			(percent)
	Discount rate				5		4		5		4.3		3.8		4		5		4		5
	Long-term rate of return on funded assets				7.25		7.25		7.25		6.3		6.4		6.6		7.25		7.25		7.25
	Long-term rate of compensation increase				5.75		5.75		5.75		5.4		5.5		5.4		5.75		5.75		5.75
Components of net periodic benefit cost					(millions of dollars)
	Service cost				677		801		665		590		697		648		140		176		134
	Interest cost				807		749		820		1,138		1,076		1,145		383		352		380
	Expected return on plan assets				-799		-835		-789		-1,193		-1,128		-1,109		-37		-41		-38
	Amortization of actuarial loss/(gain)				409		646		576		628		852		844		116		228		170
	Amortization of prior service cost				8		7		7		120		117		117		14		21		34
	Net pension enhancement and
	curtailment/settlement cost (1)				276		723		333		-		22		1,540		-		-		-
Net periodic benefit cost					1,378		2,091		1,612		1,283		1,636		3,185		616		736		680
	-1		Non-U.S. net pension enhancement and curtailment/settlement cost for 2012 includes $1,420 million (on a consolidated-company, before-tax basis) of accumulated other comprehensive income for the postretirement benefit reserves adjustment that was recycled into earnings and included in the Japan restructuring gain reported in “Other income”.
Changes in amounts recorded in accumulated
	other comprehensive income:
	Net actuarial loss/(gain)				2,494		-1,302		1,885		2,969		-1,938		1,906		1,518		-1,290		1,008
	Amortization of actuarial (loss)/gain				-685		-1,369		-909		-628		-874		-2,384		-116		-228		-170
	Prior service cost/(credit)				-25		-		-		-70		30		71		-		-		-
	Amortization of prior service (cost)/credit				-8		-7		-7		-120		-117		-117		-14		-21		-34
	Foreign exchange rate changes				-		-		-		-688		-155		271		-8		-10		3
Total recorded in other comprehensive income					1,776		-2,678		969		1,463		-3,054		-253		1,380		-1,549		807
Total recorded in net periodic benefit cost and
	other comprehensive income, before tax				3,154		-587		2,581		2,746		-1,418		2,932		1,996		-813		1,487
Costs for defined contribution plans were $393 million, $392 million and $382 million in 2014, 2013 and 2012, respectively.
A summary of the change in accumulated other comprehensive income is shown in the table below:
				Total Pension and
				Other Postretirement Benefits
				2014		2013		2012
				(millions of dollars)
(Charge)/credit to other comprehensive income, before tax
	U.S. pension			-1,776		2,678		-969
	Non-U.S. pension			-1,463		3,054		253
	Other postretirement benefits			-1,380		1,549		-807
Total (charge)/credit to other comprehensive income, before tax				-4,619		7,281		-1,523
(Charge)/credit to income tax (see Note 4)				1,549		-2,336		393
(Charge)/credit to investment in equity companies				-81		49		-49
(Charge)/credit to other comprehensive income including noncontrolling
	interests, after tax			-3,151		4,994		-1,179
Charge/(credit) to equity of noncontrolling interests				85		-279		-124
(Charge)/credit to other comprehensive income attributable to ExxonMobil				-3,066		4,715		-1,303
The Corporation’s investment strategy for benefit plan assets reflects a long-term view, a careful assessment of the risks inherent in various asset classes and broad diversification to reduce the risk of the portfolio. The benefit plan assets are primarily invested in passive equity and fixed income index funds to diversify risk while minimizing costs. The equity funds hold ExxonMobil stock only to the extent necessary to replicate the relevant equity index. The fixed income funds are largely invested in high-quality corporate and government debt securities.
Studies are periodically conducted to establish the preferred target asset allocation percentages. The target asset allocation for the U.S. benefit plans and for the non-U.S. plans in aggregate is 40 percent equity securities and 60 percent debt securities. The equity targets for the U.S. and non-U.S. plans include an allocation to private equity partnerships that primarily focus on early-stage venture capital of 5 percent and 3 percent, respectively.
The fair value measurement levels are accounting terms that refer to different methods of valuing assets. The terms do not represent the relative risk or credit quality of an investment.
The 2014 fair value of the benefit plan assets, including the level within the fair value hierarchy, is shown in the tables below:
			U.S. Pension											Non-U.S. Pension
			Fair Value Measurement											Fair Value Measurement
			at December 31, 2014, Using:											at December 31, 2014, Using:
				Quoted											Quoted
				Prices											Prices
				in Active	Significant										in Active		Significant
			Markets for			Other		Significant						Markets for				Other		Significant
				Identical	Observable			Unobservable							Identical		Observable			Unobservable
				Assets		Inputs			Inputs						Assets			Inputs			Inputs
				(Level 1)		(Level 2)			(Level 3)			Total			(Level 1)			(Level 2)			(Level 3)		Total
				(millions of dollars)
Asset category:
	Equity securities
		U.S.		-		2,331	-1		-			2,331			-			3,284	-1		-		3,284
		Non-U.S.		-		2,144	-1		-			2,144			229	-2		3,776	-1		-		4,005
	Private equity			-		-			562	-3		562			-			-			535	-3	535
	Debt securities
		Corporate		-		4,841	-4		-			4,841			-			2,686	-4		-		2,686
		Government		-		2,890	-4		-			2,890			249	-5		9,050	-4		-		9,299
		Asset-backed		-		5	-4		-			5			-			146	-4		-		146
	Real estate funds			-		-			-			-			-			-			57	-6	57
	Cash			-		131	-7		-			131			25			31	-8		-		56
Total at fair value				-		12,342			562			12,904			503			18,973			592		20,068
	Insurance contracts
		at contract value										11											27
Total plan assets												12,915											20,095
(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
(2) For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
(3) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
(4) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
(5) For corporate and government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
(6) For real estate funds, fair value is based on appraised values developed using comparable market transactions.
(7) For cash balances held in the form of short-term fund units that are redeemable at the measurement date, the fair value is treated as a Level 2 input.
(8) For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.
			Other Postretirement
				Fair Value Measurement
			at December 31, 2014, Using:
				Quoted
				Prices
				in Active			Significant
				Markets for			Other			Significant
				Identical			Observable			Unobservable
				Assets			Inputs			Inputs
				(Level 1)			(Level 2)			(Level 3)			Total
				(millions of dollars)
Asset category:
	Equity securities
		U.S.		-			106	-1		-			106
		Non-U.S.		-			75	-1		-			75
	Private equity			-			-			2	-2		2
	Debt securities
		Corporate		-			103	-3		-			103
		Government		-			171	-3		-			171
		Asset-backed		-			9	-3		-			9
	Cash			-			2			-			2
Total at fair value				-			466			2			468
For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
The change in the fair value in 2014 of Level 3 assets that use significant unobservable inputs to measure fair value is shown in the table below:
		2014
		Pension									Other
		U.S.				Non-U.S.					Postretirement
		Private				Private		Real			Private
		Equity				Equity		Estate			Equity
		(millions of dollars)
Fair value at January 1		523				502		136			9
Net realized gains/(losses)		2				23		-17			-
Net unrealized gains/(losses)		89				31		8			-
Net purchases/(sales)		-52				-21		-70			-7
Fair value at December 31		562				535		57			2
The 2013 fair value of the benefit plan assets, including the level within the fair value hierarchy, is shown in the tables below:
			U.S. Pension											Non-U.S. Pension
			Fair Value Measurement											Fair Value Measurement
			at December 31, 2013, Using:											at December 31, 2013, Using:
				Quoted											Quoted
				Prices											Prices
				in Active	Significant										in Active		Significant
			Markets for			Other		Significant						Markets for				Other		Significant
				Identical	Observable			Unobservable							Identical		Observable			Unobservable
				Assets		Inputs			Inputs						Assets			Inputs			Inputs
				(Level 1)		(Level 2)			(Level 3)			Total			(Level 1)			(Level 2)			(Level 3)		Total
			(millions of dollars)
Asset category:
	Equity securities
		U.S.		-		2,514	-1		-			2,514			-			3,046	-1		-		3,046
		Non-U.S.		-		2,622	-1		-			2,622			294	-2		5,608	-1		-		5,902
	Private equity			-		-			523	-3		523			-			-			502	-3	502
	Debt securities
		Corporate		-		3,430	-4		-			3,430			-			2,125	-4		-		2,125
		Government		-		2,056	-4		-			2,056			272	-5		7,100	-4		-		7,372
		Asset-backed		-		6	-4		-			6			-			103	-4		-		103
	Real estate funds			-		-			-			-			-			-			136	-6	136
	Cash			-		27	-7		-			27			57			20	-8		-		77
Total at fair value				-		10,655			523			11,178			623			18,002			638		19,263
	Insurance contracts
		at contract value										12											20
Total plan assets												11,190											19,283
(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
(2) For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
(3) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
(4) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
(5) For corporate and government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
(6) For real estate funds, fair value is based on appraised values developed using comparable market transactions.
(7) For cash balances held in the form of short-term fund units that are redeemable at the measurement date, the fair value is treated as a Level 2 input.
(8) For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.
			Other Postretirement
			Fair Value Measurement
			at December 31, 2013, Using:
				Quoted
				Prices
				in Active			Significant
				Markets for			Other			Significant
				Identical			Observable			Unobservable
				Assets			Inputs			Inputs
				(Level 1)			(Level 2)			(Level 3)			Total
			(millions of dollars)
Asset category:
	Equity securities
		U.S.		-			157	-1		-			157
		Non-U.S.		-			149	-1		-			149
	Private equity			-			-			9	-2		9
	Debt securities
		Corporate		-			129	-3		-			129
		Government		-			168	-3		-			168
		Asset-backed		-			4	-3		-			4
	Cash			-			4			-			4
Total at fair value				-			611			9			620
(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
(2) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
(3) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
The change in the fair value in 2013 of Level 3 assets that use significant unobservable inputs to measure fair value is shown in the table below:
		2013
		Pension									Other
		U.S.				Non-U.S.					Postretirement
		Private				Private		Real			Private
		Equity				Equity		Estate			Equity
		(millions of dollars)
Fair value at January 1		489				448		293			7
Net realized gains/(losses)		-1				11		-13			-
Net unrealized gains/(losses)		86				57		10			3
Net purchases/(sales)		-51				-14		-154			-1
Fair value at December 31		523				502		136			9
A summary of pension plans with an accumulated benefit obligation in excess of plan assets is shown in the table below:
		Pension Benefits
		U.S.					Non-U.S.
			2014		2013			2014		2013
		(millions of dollars)
For funded pension plans with an accumulated benefit obligation
	in excess of plan assets:
	Projected benefit obligation		17,505		14,737			5,031		891
	Accumulated benefit obligation		14,493		12,342			4,590		689
	Fair value of plan assets		12,915		11,189			3,890		611
For unfunded pension plans:
	Projected benefit obligation		3,024		2,567			7,839		7,133
	Accumulated benefit obligation		1,892		1,647			6,573		6,070
							Other
		Pension Benefits					Postretirement
		U.S.			Non-U.S.		Benefits
		(millions of dollars)
Estimated 2015 amortization from accumulated other comprehensive income:
	Net actuarial loss/(gain) (1)		1,001		753			211
	Prior service cost (2)		6		105			14
(1) The Corporation amortizes the net balance of actuarial losses/(gains) as a component of net periodic benefit cost over the average remaining service period of active plan participants.
(2) The Corporation amortizes prior service cost on a straight-line basis as permitted under authoritative guidance for defined benefit pension and other postretirement benefit plans.
			Pension Benefits				Other Postretirement Benefits
									Medicare
			U.S.		Non-U.S.		Gross		Subsidy Receipt
			(millions of dollars)
Contributions expected in 2015			-		560		-			-
Benefit payments expected in:
	2015		1,628		1,194		467			24
	2016		1,554		1,213		479			25
	2017		1,529		1,278		490			26
	2018		1,445		1,298		499			28
	2019		1,410		1,339		507			29
	2020 - 2024		6,714		6,988		2,613			172

Disclosures_About_Segments_And

Disclosures About Segments And Related Information	12 Months Ended
	Dec. 31, 2014
Disclosures About Segments And Related Information [Abstract]
Disclosures About Segments And Related Information	18. Disclosures about Segments and Related Information
	The Upstream, Downstream and Chemical functions best define the operating segments of the business that are reported separately. The factors used to identify these reportable segments are based on the nature of the operations that are undertaken by each segment. The Upstream segment is organized and operates to explore for and produce crude oil and natural gas. The Downstream segment is organized and operates to manufacture and sell petroleum products. The Chemical segment is organized and operates to manufacture and sell petrochemicals. These segments are broadly understood across the petroleum and petrochemical industries.
	These functions have been defined as the operating segments of the Corporation because they are the segments (1) that engage in business activities from which revenues are earned and expenses are incurred; (2) whose operating results are regularly reviewed by the Corporation’s chief operating decision maker to make decisions about resources to be allocated to the segment and to assess its performance; and (3) for which discrete financial information is available.
	Earnings after income tax include transfers at estimated market prices.
	In corporate and financing activities, interest revenue relates to interest earned on cash deposits and marketable securities. Interest expense includes non-debt-related interest expense of $129 million and $202 million in 2014 and 2012, respectively. For 2013, non-debt-related interest expense was a net credit of $123 million, primarily reflecting the effect of credits from the favorable resolution of prior year tax positions.
															Corporate
		Upstream					Downstream				Chemical					and	Corporate
		U.S.		Non-U.S.			U.S.		Non-U.S.		U.S.		Non-U.S.		Financing			Total
			(millions of dollars)
	As of December 31, 2014
	Earnings after income tax		5,197		22,351			1,618		1,427		2,804		1,511		-2,388		32,520
	Earnings of equity companies included above		1,235		10,859			29		82		186		1,377		-445		13,323
	Sales and other operating revenue (1)		14,826		22,336			118,771		199,976		15,115		23,063		18		394,105
	Intersegment revenue		7,723		38,846			17,281		44,231		10,117		8,098		274		-
	Depreciation and depletion expense		5,139		8,523			654		1,228		370		645		738		17,297
	Interest revenue		-		-			-		-		-		-		75		75
	Interest expense		40		17			6		4		-		-		219		286
	Income taxes		1,300		15,165			610		968		1,032		358		-1,418		18,015
	Additions to property, plant and equipment		9,098		19,225			1,050		1,356		1,564		564		1,399		34,256
	Investments in equity companies		5,089		10,877			69		1,006		258		3,026		-308		20,017
	Total assets		92,555		161,033			18,371		33,299		8,798		18,449		16,988		349,493
	As of December 31, 2013
	Earnings after income tax		4,191		22,650			2,199		1,250		2,755		1,073		-1,538		32,580
	Earnings of equity companies included above		1,576		11,627			-460		22		189		1,422		-449		13,927
	Sales and other operating revenue (1)		13,712		25,349			123,802		218,904		15,295		23,753		21		420,836
	Intersegment revenue		8,343		45,761			20,781		52,624		11,993		8,232		285		-
	Depreciation and depletion expense		5,170		8,277			633		1,390		378		632		702		17,182
	Interest revenue		-		-			-		-		-		-		87		87
	Interest expense		30		26			7		8		1		-		-63		9
	Income taxes		2,197		21,554			721		481		989		363		-2,042		24,263
	Additions to property, plant and equipment		7,480		26,075			616		1,072		840		272		1,386		37,741
	Investments in equity companies		4,975		9,740			62		1,749		217		3,103		-227		19,619
	Total assets		88,698		157,465			19,261		40,661		7,816		19,659		13,248		346,808
	As of December 31, 2012
	Earnings after income tax		3,925		25,970			3,575		9,615		2,220		1,678		-2,103		44,880
	Earnings of equity companies included above		1,759		11,900			6		387		183		1,267		-492		15,010
	Sales and other operating revenue (1)		11,039		27,673			125,088		248,959		14,723		24,003		24		451,509
	Intersegment revenue		8,764		47,507			20,963		62,130		12,409		9,750		258		-
	Depreciation and depletion expense		5,104		7,340			594		1,280		376		508		686		15,888
	Interest revenue		-		-			-		-		-		-		117		117
	Interest expense		37		13			3		36		-		-1		239		327
	Income taxes		2,025		25,362			1,811		1,892		755		232		-1,032		31,045
	Additions to property, plant and equipment		9,697		21,769			480		1,153		338		659		1,083		35,179
	Investments in equity companies		4,020		9,147			195		2,069		233		3,143		-277		18,530
	Total assets		86,146		140,848			18,451		40,956		7,238		18,886		21,270		333,795
	(1) Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
	Geographic
	Sales and other operating revenue (1)			2014		2013		2012
				(millions of dollars)
	United States			148,713		152,820		150,865
	Non-U.S.			245,392		268,016		300,644
		Total		394,105		420,836		451,509
	Significant non-U.S. revenue sources include:
		Canada		36,072		35,924		34,325
		United Kingdom		31,346		34,061		33,600
		Belgium		20,953		20,973		23,567
		Italy		18,880		19,273		18,228
		France		17,639		18,444		19,601
		Singapore		15,407		15,623		14,606
		Germany		14,816		15,701		15,871
	(1) Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
	Long-lived assets			2014		2013		2012
				(millions of dollars)
	United States			104,000		98,271		94,336
Non-U.S.			148,668		145,379		132,613
	Total		252,668		243,650		226,949
Significant non-U.S. long-lived assets include:
	Canada		43,858		41,522		31,979
	Australia		15,328		14,258		13,415
	Nigeria		12,265		12,343		12,216
	Singapore		9,620		9,570		9,700
	Kazakhstan		9,138		8,530		7,785
	Angola		9,057		8,262		8,238
	Papua New Guinea		6,099		5,768		4,599
	Norway		5,139		6,542		7,040

Income_SalesBased_And_Other_Ta

Income, Sales-Based And Other Taxes	12 Months Ended
	Dec. 31, 2014
Income, Sales-Based And Other Taxes [Abstract]
Income, Sales-Based And Other Taxes	19. Income, Sales-Based and Other Taxes
								2014					2013				2012
						U.S.	Non-U.S.			Total	U.S.	Non-U.S.		Total	U.S.	Non-U.S.		Total
											(millions of dollars)
	Income tax expense
		Federal and non-U.S.
			Current			1,456		14,755		16,211	1,073		22,115	23,188	1,791		25,650	27,441
			Deferred - net			900		1,398		2,298	-116		757	641	1,097		1,816	2,913
		U.S. tax on non-U.S. operations				5		-		5	37		-	37	89		-	89
				Total federal and non-U.S.		2,361		16,153		18,514	994		22,872	23,866	2,977		27,466	30,443
		State (1)				-499		-		-499	397		-	397	602		-	602
				Total income tax expense		1,862		16,153		18,015	1,391		22,872	24,263	3,579		27,466	31,045
	Sales-based taxes					6,310		23,032		29,342	5,992		24,597	30,589	5,785		26,624	32,409
	All other taxes and duties
		Other taxes and duties				378		31,908		32,286	955		32,275	33,230	1,406		34,152	35,558
		Included in production and
			manufacturing expenses			1,454		1,179		2,633	1,318		1,182	2,500	1,242		1,308	2,550
		Included in SG&A expenses				155		441		596	150		516	666	154		595	749
			Total other taxes and duties			1,987		33,528		35,515	2,423		33,973	36,396	2,802		36,055	38,857
				Total		10,159		72,713		82,872	9,806		81,442	91,248	12,166		90,145	102,311
	(1) In 2014, state taxes included a favorable adjustment of deferred taxes of approximately $830 million.
	All other taxes and duties include taxes reported in production and manufacturing and selling, general and administrative (SG&A) expenses. The above provisions for deferred income taxes include net credits of $40 million in 2014 and $310 million in 2013 and a net charge of $244 million in 2012 for the effect of changes in tax laws and rates.
	The reconciliation between income tax expense and a theoretical U.S. tax computed by applying a rate of 35 percent for 2014, 2013 and 2012 is as follows:
					2014		2013		2012
					(millions of dollars)
	Income before income taxes
		United States			9,080		9,746		11,222
		Non-U.S.			42,550		47,965		67,504
			Total		51,630		57,711		78,726
	Theoretical tax				18,071		20,199		27,554
	Effect of equity method of accounting				-4,663		-4,874		-5,254
	Non-U.S. taxes in excess of theoretical U.S. tax				5,442		10,528		8,434
	U.S. tax on non-U.S. operations				5		37		89
	State taxes, net of federal tax benefit				-324		258		391
	Other				-516		-1,885		-169
			Total income tax expense		18,015		24,263		31,045
	Effective tax rate calculation
	Income taxes				18,015		24,263		31,045
	ExxonMobil share of equity company income taxes				5,678		6,061		5,859
			Total income taxes		23,693		30,324		36,904
	Net income including noncontrolling interests				33,615		33,448		47,681
			Total income before taxes		57,308		63,772		84,585
	Effective income tax rate				41%		48%		44%
	Deferred income taxes reflect the impact of temporary differences between the amount of assets and liabilities recognized for financial reporting purposes and such amounts recognized for tax purposes.
	Deferred tax liabilities/(assets) are comprised of the following at December 31:
	Tax effects of temporary differences for:			2014		2013
				(millions of dollars)
	Property, plant and equipment			51,643		50,884
	Other liabilities			4,359		3,474
		Total deferred tax liabilities		56,002		54,358
	Pension and other postretirement benefits			-8,140		-6,573
	Asset retirement obligations			-6,162		-6,083
	Tax loss carryforwards			-4,099		-3,393
	Other assets			-6,446		-6,246
		Total deferred tax assets		-24,847		-22,295
	Asset valuation allowances			2,570		2,491
		Net deferred tax liabilities		33,725		34,554
	In 2014, asset valuation allowances of $2,570 million increased by $79 million and included additional net provisions of $340 million and effects of foreign currency translation of $(261) million.
	Deferred income tax (assets) and liabilities are included in the balance sheet as shown below. Deferred income tax (assets) and liabilities are classified as current or long term consistent with the classification of the related temporary difference – separately by tax jurisdiction.
	Balance sheet classification			2014		2013
				(millions of dollars)
	Other current assets			-2,001		-3,575
	Other assets, including intangibles, net			-3,955		-2,822
	Accounts payable and accrued liabilities			451		421
Deferred income tax liabilities			39,230		40,530
	Net deferred tax liabilities		33,725		34,554
The Corporation had $51 billion of indefinitely reinvested, undistributed earnings from subsidiary companies outside the U.S. Unrecognized deferred taxes on remittance of these funds are not expected to be material.
Unrecognized Tax Benefits. The Corporation is subject to income taxation in many jurisdictions around the world. Unrecognized tax benefits reflect the difference between positions taken or expected to be taken on income tax returns and the amounts recognized in the financial statements. The following table summarizes the movement in unrecognized tax benefits:
Gross unrecognized tax benefits		2014		2013		2012
		(millions of dollars)
Balance at January 1		7,838		7,663		4,922
	Additions based on current year's tax positions	1,454		1,460		1,662
	Additions for prior years' tax positions	448		464		2,559
	Reductions for prior years' tax positions	-532		-249		-535
	Reductions due to lapse of the statute of limitations	-117		-588		-79
	Settlements with tax authorities	-43		-849		-855
	Foreign exchange effects/other	-62		-63		-11
Balance at December 31		8,986		7,838		7,663
The gross unrecognized tax benefit balances shown above are predominantly related to tax positions that would reduce the Corporation’s effective tax rate if the positions are favorably resolved. Unfavorable resolution of these tax positions generally would not increase the effective tax rate. The 2014, 2013 and 2012 changes in unrecognized tax benefits did not have a material effect on the Corporation’s net income.
Resolution of these tax positions through negotiations with the relevant tax authorities or through litigation will take many years to complete. It is difficult to predict the timing of resolution for tax positions since such timing is not entirely within the control of the Corporation. It is reasonably possible that the total amount of unrecognized tax benefits could increase by up to 30 percent in the next 12 months, with no material impact on the Corporation’s net income.
The following table summarizes the tax years that remain subject to examination by major tax jurisdiction:
	Country of Operation	Open Tax Years
	Abu Dhabi	2012 - 2014
	Angola	2009 - 2014
	Australia:	2000 - 2003
		2005
		2008 - 2014
	Canada	2007 - 2014
	Equatorial Guinea	2007 - 2014
	Malaysia	2008 - 2014
	Nigeria	2004 - 2014
	Norway	2005 - 2014
	Qatar	2008 - 2014
	Russia	2011 - 2014
	United Kingdom	2010 - 2014
	United States	2006 - 2014
The Corporation classifies interest on income tax-related balances as interest expense or interest income and classifies tax-related penalties as operating expense.
The Corporation incurred $42 million in interest expense on income tax reserves in 2014. For 2013, the Corporation’s net interest expense was a credit of $207 million, reflecting the effect of credits from the favorable resolution of prior year tax positions. The Corporation incurred $46 million in interest expense in 2012. The related interest payable balances were $205 million and $156 million at December 31, 2014, and 2013, respectively.

Summary_Of_Accounting_Policies1

Summary Of Accounting Policies (Policy)	12 Months Ended
	Dec. 31, 2014
Summary Of Accounting Policies [Abstract]
Principles Of Consolidation	Principles of Consolidation. The Consolidated Financial Statements include the accounts of subsidiaries the Corporation controls. They also include the Corporation’s share of the undivided interest in certain upstream assets, liabilities, revenues and expenses.
	Amounts representing the Corporation’s interest in entities that it does not control, but over which it exercises significant influence, are included in “Investments, advances and long-term receivables.” The Corporation’s share of the net income of these companies is included in the Consolidated Statement of Income caption “Income from equity affiliates.”
	Majority ownership is normally the indicator of control that is the basis on which subsidiaries are consolidated. However, certain factors may indicate that a majority-owned investment is not controlled and therefore should be accounted for using the equity method of accounting. These factors occur where the minority shareholders are granted by law or by contract substantive participating rights. These include the right to approve operating policies, expense budgets, financing and investment plans, and management compensation and succession plans.
	The Corporation’s share of the cumulative foreign exchange translation adjustment for equity method investments is reported in Accumulated Other Comprehensive Income.
	Evidence of loss in value that might indicate impairment of investments in companies accounted for on the equity method is assessed to determine if such evidence represents a loss in value of the Corporation’s investment that is other than temporary. Examples of key indicators include a history of operating losses, negative earnings and cash flow outlook, significant downward revisions to oil and gas reserves, and the financial condition and prospects for the investee’s business segment or geographic region. If evidence of an other than temporary loss in fair value below carrying amount is determined, an impairment is recognized. In the absence of market prices for the investment, discounted cash flows are used to assess fair value.
Revenue Recognition	Revenue Recognition. The Corporation generally sells crude oil, natural gas and petroleum and chemical products under short-term agreements at prevailing market prices. In some cases (e.g., natural gas), products may be sold under long-term agreements, with periodic price adjustments. Revenues are recognized when the products are delivered, which occurs when the customer has taken title and has assumed the risks and rewards of ownership, prices are fixed or determinable and collectibility is reasonably assured.
	Revenues from the production of natural gas properties in which the Corporation has an interest with other producers are recognized on the basis of the Corporation’s net working interest. Differences between actual production and net working interest volumes are not significant.
	Purchases and sales of inventory with the same counterparty that are entered into in contemplation of one another are combined and recorded as exchanges measured at the book value of the item sold.
Sales-Based Taxes	Sales-Based Taxes. The Corporation reports sales, excise and value-added taxes on sales transactions on a gross basis in the Consolidated Statement of Income (included in both revenues and costs).
Derivative Instruments	Derivative Instruments. The Corporation makes limited use of derivative instruments. The Corporation does not engage in speculative derivative activities or derivative trading activities, nor does it use derivatives with leveraged features. When the Corporation does enter into derivative transactions, it is to offset exposures associated with interest rates, foreign currency exchange rates and hydrocarbon prices that arise from existing assets, liabilities and forecasted transactions.
	The gains and losses resulting from changes in the fair value of derivatives are recorded in income. In some cases, the Corporation designates derivatives as fair value hedges, in which case the gains and losses are offset in income by the gains and losses arising from changes in the fair value of the underlying hedged item.
Fair Value	Fair Value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. Hierarchy Levels 1, 2 and 3 are terms for the priority of inputs to valuation techniques used to measure fair value. Hierarchy Level 1 inputs are quoted prices in active markets for identical assets or liabilities. Hierarchy Level 2 inputs are inputs other than quoted prices included within Level 1 that are directly or indirectly observable for the asset or liability. Hierarchy Level 3 inputs are inputs that are not observable in the market.
Inventories	Inventories. Crude oil, products and merchandise inventories are carried at the lower of current market value or cost (generally determined under the last-in, first-out method – LIFO). Inventory costs include expenditures and other charges (including depreciation) directly and indirectly incurred in bringing the inventory to its existing condition and location. Selling expenses and general and administrative expenses are reported as period costs and excluded from inventory cost. Inventories of materials and supplies are valued at cost or less.
Property, Plant And Equipment	Property, Plant and Equipment. Depreciation, depletion and amortization, based on cost less estimated salvage value of the asset, are primarily determined under either the unit-of-production method or the straight-line method, which is based on estimated asset service life taking obsolescence into consideration. Maintenance and repairs, including planned major maintenance, are expensed as incurred. Major renewals and improvements are capitalized and the assets replaced are retired.
	The Corporation uses the “successful efforts” method to account for its exploration and production activities. Under this method, costs are accumulated on a field-by-field basis. Costs incurred to purchase, lease, or otherwise acquire a property (whether unproved or proved) are capitalized when incurred. Exploratory well costs are carried as an asset when the well has found a sufficient quantity of reserves to justify its completion as a producing well and where the Corporation is making sufficient progress assessing the reserves and the economic and operating viability of the project. Exploratory well costs not meeting these criteria are charged to expense. Other exploratory expenditures, including geophysical costs and annual lease rentals, are expensed as incurred. Development costs including costs of productive wells and development dry holes are capitalized.
	Acquisition costs of proved properties are amortized using a unit-of-production method, computed on the basis of total proved oil and gas reserves. Capitalized exploratory drilling and development costs associated with productive depletable extractive properties are amortized using unit-of-production rates based on the amount of proved developed reserves of oil, gas and other minerals that are estimated to be recoverable from existing facilities using current operating methods. Under the unit-of-production method, oil and gas volumes are considered produced once they have been measured through meters at custody transfer or sales transaction points at the outlet valve on the lease or field storage tank.
	Production involves lifting the oil and gas to the surface and gathering, treating, field processing and field storage of the oil and gas. The production function normally terminates at the outlet valve on the lease or field production storage tank. Production costs are those incurred to operate and maintain the Corporation’s wells and related equipment and facilities and are expensed as incurred. They become part of the cost of oil and gas produced. These costs, sometimes referred to as lifting costs, include such items as labor costs to operate the wells and related equipment; repair and maintenance costs on the wells and equipment; materials, supplies and energy costs required to operate the wells and related equipment; and administrative expenses related to the production activity.
	Proved oil and gas properties held and used by the Corporation are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amounts may not be recoverable. Assets are grouped at the lowest level for which there are identifiable cash flows that are largely independent of the cash flows of other groups of assets.
	The Corporation estimates the future undiscounted cash flows of the affected properties to judge the recoverability of carrying amounts. Cash flows used in impairment evaluations are developed using annually updated corporate plan investment evaluation assumptions for crude oil and natural gas commodity prices, refining and chemical margins and foreign currency exchange rates. Annual volumes are based on field production profiles, which are also updated annually. Prices for other petroleum and chemical products are based on corporate plan assumptions developed annually by major region and also for investment evaluation purposes. Cash flow estimates for impairment testing exclude derivative instruments.
	Impairment analyses are generally based on proved reserves. Where probable reserves exist, an appropriately risk-adjusted amount of these reserves may be included in the impairment evaluation. An asset group would be impaired if the undiscounted cash flows were less than its carrying value. Impairments are measured by the amount the carrying value exceeds fair value.
	Significant unproved properties are assessed for impairment individually, and valuation allowances against the capitalized costs are recorded based on the estimated economic chance of success and the length of time that the Corporation expects to hold the properties. Properties that are not individually significant are aggregated by groups and amortized based on development risk and average holding period. The valuation allowances are reviewed at least annually.
	Gains on sales of proved and unproved properties are only recognized when there is neither uncertainty about the recovery of costs applicable to any interest retained nor any substantial obligation for future performance by the Corporation.
	Losses on properties sold are recognized when incurred or when the properties are held for sale and the fair value of the properties is less than the carrying value.
	Interest costs incurred to finance expenditures during the construction phase of multiyear projects are capitalized as part of the historical cost of acquiring the constructed assets. The project construction phase commences with the development of the detailed engineering design and ends when the constructed assets are ready for their intended use. Capitalized interest costs are included in property, plant and equipment and are depreciated over the service life of the related assets.
Asset Retirement Obligations And Environmental Liabilities	Asset Retirement Obligations and Environmental Liabilities. The Corporation incurs retirement obligations for certain assets. The fair values of these obligations are recorded as liabilities on a discounted basis, which is typically at the time the assets are installed. The costs associated with these liabilities are capitalized as part of the related assets and depreciated. Over time, the liabilities are accreted for the change in their present value.
	Liabilities for environmental costs are recorded when it is probable that obligations have been incurred and the amounts can be reasonably estimated. These liabilities are not reduced by possible recoveries from third parties and projected cash expenditures are not discounted.
Foreign Currency Translation	Foreign Currency Translation. The Corporation selects the functional reporting currency for its international subsidiaries based on the currency of the primary economic environment in which each subsidiary operates.
	Downstream and Chemical operations primarily use the local currency. However, the U.S. dollar is used in countries with a history of high inflation (primarily in Latin America) and Singapore, which predominantly sells into the U.S. dollar export market. Upstream operations which are relatively self-contained and integrated within a particular country, such as Canada, the United Kingdom, Norway and continental Europe, use the local currency. Some Upstream operations, primarily in Asia and Africa, use the U.S. dollar because they predominantly sell crude and natural gas production into U.S. dollar-denominated markets.
	For all operations, gains or losses from remeasuring foreign currency transactions into the functional currency are included in income.
Stock-Based Payments	Stock-Based Payments. The Corporation awards stock-based compensation to employees in the form of restricted stock and restricted stock units. Compensation expense is measured by the price of the stock at the date of grant and is recognized in income over the requisite service period.

Miscellaneous_Financial_Inform1

Miscellaneous Financial Information (Tables)	12 Months Ended
	Dec. 31, 2014
Miscellaneous Financial Information [Abstract]
Crude Oil, Products And Merchandise			2014	2013
			(billions of dollars)
	Petroleum products		4.1	3.9
	Crude oil		4.6	4.7
	Chemical products		2.9	2.9
	Gas/other		0.8	0.6
		Total	12.4	12.1

Other_Comprehensive_Income_Inf1

Other Comprehensive Income Information (Tables)	12 Months Ended
	Dec. 31, 2014
Other Comprehensive Income Information [Abstract]
Schedule Of Accumulated Other Comprehensive Income Information			Cumulative			Post-
			Foreign			retirement			Unrealized
			Exchange			Benefits			Change in
	ExxonMobil Share of Accumulated Other		Translation			Reserves			Stock
	Comprehensive Income		Adjustment			Adjustment			Investments	Total
			(millions of dollars)
	Balance as of December 31, 2011		4,168			-13,291			-	-9,123
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	842			-3,402			-	-2,560
	Amounts reclassified from accumulated other
		comprehensive income	-2,600			2,099			-	-501
	Total change in accumulated other comprehensive income		-1,758			-1,303			-	-3,061
	Balance as of December 31, 2012		2,410			-14,594			-	-12,184
	Balance as of December 31, 2012		2,410			-14,594			-	-12,184
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	-3,233			2,963			-	-270
	Amounts reclassified from accumulated other
		comprehensive income	-23			1,752			-	1,729
	Total change in accumulated other comprehensive income		-3,256			4,715			-	1,459
	Balance as of December 31, 2013		-846			-9,879			-	-10,725
	Balance as of December 31, 2013		-846			-9,879			-	-10,725
	Current period change excluding amounts reclassified
		from accumulated other comprehensive income	-5,258			-4,132			-63	-9,453
	Amounts reclassified from accumulated other
		comprehensive income	152			1,066			3	1,221
	Total change in accumulated other comprehensive income		-5,106			-3,066			-60	-8,232
	Balance as of December 31, 2014		-5,952			-12,945			-60	-18,957
Reclassification Out Of Accumulated Other Comprehensive Income	Amounts Reclassified Out of Accumulated Other
	Comprehensive Income - Before-tax Income/(Expense)			2014		2013		2012
				(millions of dollars)
	Foreign exchange translation gain/(loss) included in net income
		(Statement of Income line: Other income)		-152		23		4,352
	Amortization and settlement of postretirement benefits reserves
		adjustment included in net periodic benefit costs (1)		-1,571		-2,616		-3,621
	Realized change in fair value of stock investments included in net income
		(Statement of Income line: Other income)		-5		-		-
	(1) These accumulated other comprehensive income components are included in the computation of net periodic pension cost. (See Note 17 – Pension and Other Postretirement Benefits for additional details.)
Schedule Of Income Tax (Expense)/Credit For Components Of Other Comprehensive Income	Income Tax (Expense)/Credit For
	Components of Other Comprehensive Income		2014		2013		2012
			(millions of dollars)
	Foreign exchange translation adjustment		292		218		-236
	Postretirement benefits reserves adjustment (excluding amortization)		2,009		-1,540		1,619
	Amortization and settlement of postretirement benefits reserves
		adjustment included in net periodic benefit costs	-460		-796		-1,226
	Unrealized change in fair value of stock investments		34		-		-
	Realized change in fair value of stock investments included in net income		-2		-		-
	Total		1,873		-2,118		157

Cash_Flow_Information_Tables

Cash Flow Information (Tables)	12 Months Ended
	Dec. 31, 2014
Cash Flow Information [Abstract]
Cash payments for interest and income taxes		2014	2013	2012
		(millions of dollars)
	Cash payments for interest	380	426	555
	Cash payments for income taxes	18,085	25,066	24,349

Additional_Working_Capital_Inf1

Additional Working Capital Information (Tables)	12 Months Ended
	Dec. 31, 2014
Additional Working Capital Information [Abstract]
Schedule Of Notes, Accounts Receivable And Payable, Loans Payable, And Accrued Liabilities				Dec. 31	Dec. 31
				2014	2013
				(millions of dollars)
	Notes and accounts receivable
		Trade, less reserves of $113 million and $112 million		18,541	25,993
		Other, less reserves of $48 million and $28 million		9,468	7,159
			Total	28,009	33,152
	Notes and loans payable
		Bank loans		473	723
		Commercial paper		16,225	14,051
		Long-term debt due within one year		770	1,034
			Total	17,468	15,808
	Accounts payable and accrued liabilities
		Trade payables		25,286	30,920
		Payables to equity companies		6,589	6,587
		Accrued taxes other than income taxes		3,290	3,883
		Other		7,062	6,695
			Total	42,227	48,085

Equity_Company_Information_Tab

Equity Company Information (Tables)	12 Months Ended
	Dec. 31, 2014
Equity Company Information [Abstract]
Schedule Of Equity Company Financial Summary				2014			2013			2012
	Equity Company				ExxonMobil			ExxonMobil			ExxonMobil
	Financial Summary			Total		Share	Total		Share	Total		Share
				(millions of dollars)
	Total revenues			183,708		55,855	236,161		68,084	224,953		67,572
	Income before income taxes			65,549		19,014	69,454		19,999	69,411		20,882
	Income taxes			20,520		5,684	21,618		6,069	20,703		5,868
		Income from equity affiliates		45,029		13,330	47,836		13,930	48,708		15,014
	Current assets			49,905		16,802	62,398		19,545	59,612		18,483
	Long-term assets			110,754		33,619	116,450		35,695	111,131		33,798
		Total assets		160,659		50,421	178,848		55,240	170,743		52,281
	Current liabilities			37,333		11,472	54,550		15,243	49,698		14,265
	Long-term liabilities			66,231		19,470	68,857		20,873	68,855		19,715
		Net assets		57,095		19,479	55,441		19,124	52,190		18,301
Schedule Of The Corporation's Percentage Ownership Interest			Percentage
			Ownership
			Interest
		Upstream
		Aera Energy LLC	48
		BEB Erdgas und Erdoel GmbH & Co. KG	50
		Cameroon Oil Transportation Company S.A.	41
		Cross Timbers Energy, LLC	50
		Golden Pass LNG Terminal LLC	18
		Karmorneftegaz Holding SARL	33
		Marine Well Containment Company LLC	10
		Nederlandse Aardolie Maatschappij B.V.	50
		Qatar Liquefied Gas Company Limited	10
		Qatar Liquefied Gas Company Limited (2)	24
		Ras Laffan Liquefied Natural Gas Company Limited	25
		Ras Laffan Liquefied Natural Gas Company Limited (II)	31
		Ras Laffan Liquefied Natural Gas Company Limited (3)	30
		South Hook LNG Terminal Company Limited	24
		Tengizchevroil, LLP	25
		Terminale GNL Adriatico S.r.l.	71
		Downstream
		Chalmette Refining, LLC	50
		Fujian Refining & Petrochemical Co. Ltd.	25
		Saudi Aramco Mobil Refinery Company Ltd.	50
		Chemical
		Al-Jubail Petrochemical Company	50
		Infineum Holdings B.V.	50
		Infineum USA L.P.	50
		Saudi Yanbu Petrochemical Co.	50

Investments_Advances_And_LongT1

Investments, Advances And Long-Term Receivables (Tables)	12 Months Ended
	Dec. 31, 2014
Investments, Advances And Long-Term Receivables [Abstract]
Schedule Of Investments, Advances And Long-Term Receivables				Dec. 31,	Dec. 31,
				2014	2013
				(millions of dollars)
	Companies carried at equity in underlying assets
		Investments		20,017	19,619
		Advances		9,818	10,476
			Total equity company investments and advances	29,835	30,095
	Companies carried at cost or less and stock investments carried at fair value			526	115
	Long-term receivables and miscellaneous investments at cost or less, net of reserves
		of $2,662 million and $2,938 million		4,878	6,118
			Total	35,239	36,328

Property_Plant_And_Equipment_A1

Property, Plant And Equipment And Asset Retirement Obligations (Tables)	12 Months Ended
	Dec. 31, 2014
Property, Plant And Equipment And Asset Retirement Obligations [Abstract]
Property, Plant And Equipment			31-Dec-14		31-Dec-13
	Property, Plant and Equipment		Cost	Net	Cost	Net
			(millions of dollars)
	Upstream		347,170	205,308	336,359	197,554
	Downstream		53,327	22,639	54,456	23,219
	Chemical		30,717	14,918	29,487	13,965
	Other		15,575	9,803	14,215	8,912
		Total	446,789	252,668	434,517	243,650
Asset Retirement Obligations			2014	2013
			(millions of dollars)
	Beginning balance		12,988	11,973
		Accretion expense and other provisions	871	785
		Reduction due to property sales	-151	-97
		Payments made	-724	-664
		Liabilities incurred	122	603
		Foreign currency translation	-908	-344
		Revisions	1,226	732
	Ending balance		13,424	12,988

Accounting_For_Suspended_Explo1

Accounting For Suspended Exploratory Well Costs (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting For Suspended Exploratory Well Costs [Abstract]
Change In Capitalized Suspended Exploratory Well Costs				2014		2013	2012
				(millions of dollars)
	Balance beginning at January 1			2,707		2,679	2,881
		Additions pending the determination of proved reserves		1,095		293	868
		Charged to expense		-28		-52	-95
		Reclassifications to wells, facilities and equipment based on the
			determination of proved reserves	-160		-107	-631
		Divestments/Other		-27		-106	-344
	Ending balance at December 31			3,587		2,707	2,679
	Ending balance attributed to equity companies included above			645		13	3
Period End Capitalized Suspended Exploratory Well Costs				2014		2013	2012
				(millions of dollars)
	Capitalized for a period of one year or less			1,095		293	866
		Capitalized for a period of between one and five years		1,659		1,705	1,176
		Capitalized for a period of between five and ten years		544		470	401
		Capitalized for a period of greater than ten years		289		239	236
	Capitalized for a period greater than one year - subtotal			2,492		2,414	1,813
			Total	3,587		2,707	2,679
Number Of Projects With Suspended Exploratory Well Costs				2014		2013	2012
	Number of projects with first capitalized well drilled in the preceding 12 months			8		8	10
	Number of projects that have exploratory well costs capitalized for a period
		of greater than 12 months		53		50	45
			Total	61		58	55
Additional Detail For The 38 Projects With Completed Exploratory Activity Progressing Toward Development				Years
			Dec. 31,	Wells
	Country/Project		2014	Drilled	Comment
		(millions of dollars)
	Angola
	- Kaombo Split Hub Phase 2		20	2005 - 2006	Evaluating development plan to tie into planned production facilities.
	- Perpetua-Zinia-Acacia		15	2008 - 2009	Oil field near Pazflor development, awaiting capacity in existing/planned infrastructure.
	Australia
	- East Pilchard		8	2001	Gas field near Kipper/Tuna development, awaiting capacity in existing/planned
					infrastructure.
	- SE Longtom		12	2010	Gas field near Tuna development, awaiting capacity in existing/planned infrastructure.
	- SE Remora		38	2010	Gas field near Marlin development, awaiting capacity in existing/planned infrastructure.
	Indonesia
	- Alas Tua West		16	2010	Evaluating development plan to tie into planned production facilities.
	- Cepu Gas		28	2008 - 2011	Development activity under way, while continuing commercial discussions with the
					government.
	- Kedung Keris		11	2011	Evaluating development plan to tie into planned production facilities.
	- Natuna		118	1981 - 1983	Development activity under way, while continuing discussions with the government
					on contract terms pursuant to executed Heads of Agreement.
	Kazakhstan
	- Kairan		53	2004 - 2007	Evaluating commercialization and field development alternatives, while continuing
					discussions with the government regarding the development plan.
	Malaysia
	- Besar		18	1992 - 2010	Gas field off the east coast of Malaysia; progressing development plan.
	- Bindu		2	1995	Awaiting capacity in existing/planned infrastructure.
	Nigeria
	- Bolia		15	2002 - 2006	Evaluating development plan, while continuing discussions with the government
					regarding regional hub strategy.
	- Bosi		79	2002 - 2006	Development activity under way, while continuing discussions with the government
					regarding development plan.
	- Bosi Central		16	2006	Development activity under way, while continuing discussions with the government
					regarding development plan.
	- Erha Northeast		26	2008	Evaluating development plan for tieback to existing production facilities.
	- Owowo		50	2009 - 2012	Continuing discussions with the government regarding contract terms.
	- Pegi		32	2009	Awaiting capacity in existing/planned infrastructure.
	- Satellite Field		12	2013	Evaluating development plan to tie into planned production facilities.
	Development Phase 2
	- Other (4 projects)		14	2002	Evaluating and pursuing development of several additional discoveries.
	Norway
	- Gamma		15	2008 - 2009	Evaluating development plan for tieback to existing production facilities.
	- Lavrans		18	1995 - 1999	Evaluating development plan, awaiting capacity in existing Kristin production facility.
	- Other (7 projects)		29	2008 - 2013	Evaluating development plans, including potential for tieback to existing production
					facilities.
	Papua New Guinea
	- Juha		28	2007	Progressing development plans to tie into existing LNG facilities.
	- P'nyang		58	2012	Evaluating development alternatives to tie into existing/planned infrastructure.
	Republic of Congo
	- Mer Tres Profonde Sud		56	2000 - 2007	Evaluating development alternatives, while continuing discussions with the government
					regarding development plan.
	United Kingdom
	- Phyllis		8	2004	Evaluating development plan for tieback to existing production facilities.
	United States
	- Hadrian North		209	2010 - 2013	Evaluating development plan to tie into existing production facilities.
	- Tip Top		31	2009	Evaluating development concept and requisite facility upgrades.
	Total 2014 (38 projects)		1,035

Leased_Facilities_Tables

Leased Facilities (Tables)	12 Months Ended
	Dec. 31, 2014
Leased Facilities [Abstract]
Leased Facilities						Related
				Lease Payments		Sublease
				Under Minimum		Rental
				Commitments		Income
				(millions of dollars)
		2015		2,034		31
		2016		1,379		7
		2017		774		6
		2018		418		3
		2019		312		3
		2020 and beyond		1,296		20
		Total		6,213		70
Net Rental Cost			2014	2013	2012
			(millions of dollars)
	Rental cost		4,077	3,841	3,851
	Less sublease rental income		52	44	44
	Net rental cost		4,025	3,797	3,807

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2014
Earnings Per Share [Abstract]
Earnings Per Share Computation		2014	2013	2012
	Earnings per common share
	Net income attributable to ExxonMobil (millions of dollars)	32,520	32,580	44,880
	Weighted average number of common shares outstanding (millions of shares)	4,282	4,419	4,628
	Earnings per common share (dollars) (1)	7.6	7.37	9.7
	Dividends paid per common share (dollars)	2.7	2.46	2.18
	(1) The earnings per common share and earnings per common share - assuming dilution are the same in each period shown.

LongTerm_Debt_Tables

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2014
Long-Term Debt [Abstract]
Summarized Long-Term Debt					2014	2013
					(millions of dollars)
		Exxon Mobil Corporation
			0.921% notes due 2017		1,500	-
			Floating-rate notes due 2017 (1)		750	-
			1.819% notes due 2019		1,750	-
			Floating-rate notes due 2019 (2)		500	-
			3.176% notes due 2024		1,000	-
		XTO Energy Inc. (3)
			5.000% senior notes due 2015		-	132
			5.300% senior notes due 2015		-	243
			5.650% senior notes due 2016		207	212
			6.250% senior notes due 2017		477	489
			5.500% senior notes due 2018		383	389
			6.500% senior notes due 2018		474	485
			6.100% senior notes due 2036		199	200
			6.750% senior notes due 2037		309	312
			6.375% senior notes due 2038		236	238
		Mobil Producing Nigeria Unlimited (4)
			Variable notes due 2015-2019		399	742
		Esso (Thailand) Public Company Ltd. (5)
			Variable notes due 2015-2019		121	177
		Mobil Corporation
			8.625% debentures due 2021		249	249
		Industrial revenue bonds due 2015-2051 (6)			2,611	2,527
		Other U.S. dollar obligations (7)			104	112
		Other foreign currency obligations			9	9
		Capitalized lease obligations (8)			375	375
				Total long-term debt	11,653	6,891
	(1) Average effective interest rate of 0.3% in 2014.
	(2) Average effective interest rate of 0.4% in 2014.
	(3) Includes premiums of $219 million in 2014 and $271 million in 2013.
	(4) Average effective interest rate of 4.5% in 2014 and 4.6% in 2013.
	(5) Average effective interest rate of 2.4% in 2014 and 3.3% in 2013.
	(6) Average effective interest rate of 0.03% in 2014 and 0.06% in 2013.
	(7) Average effective interest rate of 4.2% in 2014 and 4.4% in 2013.
	(8) Average imputed interest rate of 7.0% in 2014 and 7.8% in 2013.

Incentive_Program_Tables

Incentive Program (Tables)	12 Months Ended
	Dec. 31, 2014
Incentive Program [Abstract]
Summary Of Restricted Stock And Units Outstanding		2014
				Weighted Average
				Grant-Date
	Restricted stock and units outstanding	Shares		Fair Value per Share
		(thousands)		(dollars)
	Issued and outstanding at January 1	45,207			78.29
	2013 award issued in 2014	9,705			94.47
	Vested	-10,286			79.89
	Forfeited	-187			78.89
	Issued and outstanding at December 31	44,439			81.45
Grant Value Of Restricted Stock And Units
	Value of restricted stock and units		2014	2013		2012
	Grant price (dollars)		95.2	94.47		87.24
	Value at date of grant:		(millions of dollars)
	Restricted stock and units settled in stock		858	843		797
	Units settled in cash		73	76		77
	Total value		931	919		874

Litigation_And_Other_Contingen1

Litigation And Other Contingencies (Tables)	12 Months Ended
	Dec. 31, 2014
Litigation And Other Contingencies [Abstract]
Schedule Of Guarantees								Dec. 31, 2014
				Equity Company			Other Third-Party
				Obligations (1)			Obligations			Total
							(millions of dollars)
	Guarantees
		Debt-related			3,506			41		3,547
		Other			2,920			3,982		6,902
			Total		6,426			4,023		10,449
	(1) ExxonMobil share.
Unconditional Purchase Obligations			Payments Due by Period
					2016-	2020 and
			2015		2019	Beyond			Total
			(millions of dollars)
	Unconditional purchase obligations (1)		150		608		337		1,095
	(1) Undiscounted obligations of $1,095 million mainly pertain to pipeline throughput agreements and include $433 million of obligations to equity companies. The present value of these commitments, which excludes imputed interest of $168 million, totaled $927 million.

Pension_And_Other_Postretireme1

Pension And Other Postretirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2014
Pension And Other Postretirement Benefits [Abstract]
Change In Benefit Obligation Of Pension And Other Postretirement Benefits				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(percent)
	Weighted-average assumptions used to determine
		benefit obligations at December 31
		Discount rate		4		5		3.1		4.3		4		5
		Long-term rate of compensation increase		5.75		5.75		5.3		5.4		5.75		5.75
				(millions of dollars)
	Change in benefit obligation
		Benefit obligation at January 1		17,304		19,779		27,357		28,670		7,868		9,058
		Service cost		677		801		590		697		140		176
		Interest cost		807		749		1,138		1,076		383		352
		Actuarial loss/(gain)		3,192		-1,520		4,929		-1,454		1,522		-1,267
		Benefits paid (1) (2)		-1,427		-2,520		-1,366		-1,311		-525		-511
		Foreign exchange rate changes		-		-		-2,540		-284		-48		-43
		Amendments, divestments and other		-24		15		-61		-37		96		103
	Benefit obligation at December 31			20,529		17,304		30,047		27,357		9,436		7,868
	Accumulated benefit obligation at December 31			16,385		13,989		26,318		23,949		-		-
	(1) Benefit payments for funded and unfunded plans.
	(2) For 2014 and 2013, other postretirement benefits paid are net of $21 million and $20 million of Medicare subsidy receipts, respectively.
Change In Plan Assets Of Pension And Other Postretirement Benefits				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(millions of dollars)
	Change in plan assets
		Fair value at January 1		11,190		12,632		19,283		18,090		620		581
		Actual return on plan assets		1,497		617		3,153		1,604		41		64
		Foreign exchange rate changes		-		-		-1,738		-270		-		-
		Company contribution		1,476		101		554		919		31		35
		Benefits paid (1)		-1,248		-2,171		-912		-869		-224		-60
		Other		-		11		-245		-191		-		-
	Fair value at December 31			12,915		11,190		20,095		19,283		468		620
	(1) Benefit payments for funded plans.
Summary Of Assets In Excess Of/(Less Than) Benefit Obligation				Pension Benefits
				U.S.				Non-U.S.
				2014		2013		2014		2013
				(millions of dollars)
	Assets in excess of/(less than) benefit obligation
		Balance at December 31
		Funded plans		-4,590		-3,547		-2,113		-941
		Unfunded plans		-3,024		-2,567		-7,839		-7,133
	Total			-7,614		-6,114		-9,952		-8,074
Amounts Recorded In Balance Sheet And Other Comprehensive Income				Pension Benefits								Other Postretirement
				U.S.				Non-U.S.				Benefits
				2014		2013		2014		2013		2014		2013
				(millions of dollars)
	Assets in excess of/(less than) benefit obligation
		Balance at December 31 (1)		-7,614		-6,114		-9,952		-8,074		-8,968		-7,248
	Amounts recorded in the consolidated balance
		sheet consist of:
		Other assets		-		1		302		201		-		-
		Current liabilities		-340		-275		-325		-358		-369		-359
		Postretirement benefits reserves		-7,274		-5,840		-9,929		-7,917		-8,599		-6,889
	Total recorded			-7,614		-6,114		-9,952		-8,074		-8,968		-7,248
	Amounts recorded in accumulated other
		comprehensive income consist of:
		Net actuarial loss/(gain)		6,589		4,780		9,642		7,943		2,997		1,603
		Prior service cost		27		60		429		665		51		65
	Total recorded in accumulated other
		comprehensive income		6,616		4,840		10,071		8,608		3,048		1,668
	(1) Fair value of assets less benefit obligation shown on the preceding page.
Schedule Of Assumptions, Components Of Benefit Cost And Amounts Recorded In Accumulated Other Comprehensive Income For Pension And Other Postretirement Benefits																		Other
						Pension Benefits												Postretirement
						U.S.						Non-U.S.						Benefits
						2014		2013		2012		2014		2013		2012		2014		2013		2012
	Weighted-average assumptions used to
		determine net periodic benefit cost for
		years ended December 31			(percent)
		Discount rate				5		4		5		4.3		3.8		4		5		4		5
		Long-term rate of return on funded assets				7.25		7.25		7.25		6.3		6.4		6.6		7.25		7.25		7.25
		Long-term rate of compensation increase				5.75		5.75		5.75		5.4		5.5		5.4		5.75		5.75		5.75
	Components of net periodic benefit cost					(millions of dollars)
		Service cost				677		801		665		590		697		648		140		176		134
		Interest cost				807		749		820		1,138		1,076		1,145		383		352		380
		Expected return on plan assets				-799		-835		-789		-1,193		-1,128		-1,109		-37		-41		-38
		Amortization of actuarial loss/(gain)				409		646		576		628		852		844		116		228		170
		Amortization of prior service cost				8		7		7		120		117		117		14		21		34
		Net pension enhancement and
		curtailment/settlement cost (1)				276		723		333		-		22		1,540		-		-		-
	Net periodic benefit cost					1,378		2,091		1,612		1,283		1,636		3,185		616		736		680
		-1		Non-U.S. net pension enhancement and curtailment/settlement cost for 2012 includes $1,420 million (on a consolidated-company, before-tax basis) of accumulated other comprehensive income for the postretirement benefit reserves adjustment that was recycled into earnings and included in the Japan restructuring gain reported in “Other income”.
	Changes in amounts recorded in accumulated
		other comprehensive income:
		Net actuarial loss/(gain)				2,494		-1,302		1,885		2,969		-1,938		1,906		1,518		-1,290		1,008
		Amortization of actuarial (loss)/gain				-685		-1,369		-909		-628		-874		-2,384		-116		-228		-170
		Prior service cost/(credit)				-25		-		-		-70		30		71		-		-		-
		Amortization of prior service (cost)/credit				-8		-7		-7		-120		-117		-117		-14		-21		-34
		Foreign exchange rate changes				-		-		-		-688		-155		271		-8		-10		3
	Total recorded in other comprehensive income					1,776		-2,678		969		1,463		-3,054		-253		1,380		-1,549		807
	Total recorded in net periodic benefit cost and
		other comprehensive income, before tax				3,154		-587		2,581		2,746		-1,418		2,932		1,996		-813		1,487
Summary Of Change In Accumulated Other Comprehensive Income					Total Pension and
					Other Postretirement Benefits
					2014		2013		2012
					(millions of dollars)
	(Charge)/credit to other comprehensive income, before tax
		U.S. pension			-1,776		2,678		-969
		Non-U.S. pension			-1,463		3,054		253
		Other postretirement benefits			-1,380		1,549		-807
	Total (charge)/credit to other comprehensive income, before tax				-4,619		7,281		-1,523
	(Charge)/credit to income tax (see Note 4)				1,549		-2,336		393
	(Charge)/credit to investment in equity companies				-81		49		-49
	(Charge)/credit to other comprehensive income including noncontrolling
		interests, after tax			-3,151		4,994		-1,179
	Charge/(credit) to equity of noncontrolling interests				85		-279		-124
	(Charge)/credit to other comprehensive income attributable to ExxonMobil				-3,066		4,715		-1,303
Fair Value Of The Benefit Plan Assets (Pension)				U.S. Pension											Non-U.S. Pension
				Fair Value Measurement											Fair Value Measurement
				at December 31, 2014, Using:											at December 31, 2014, Using:
					Quoted											Quoted
					Prices											Prices
					in Active	Significant										in Active		Significant
				Markets for			Other		Significant						Markets for				Other		Significant
					Identical	Observable			Unobservable							Identical		Observable			Unobservable
					Assets		Inputs			Inputs						Assets			Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)			Total			(Level 1)			(Level 2)			(Level 3)		Total
					(millions of dollars)
	Asset category:
		Equity securities
			U.S.		-		2,331	-1		-			2,331			-			3,284	-1		-		3,284
			Non-U.S.		-		2,144	-1		-			2,144			229	-2		3,776	-1		-		4,005
		Private equity			-		-			562	-3		562			-			-			535	-3	535
		Debt securities
			Corporate		-		4,841	-4		-			4,841			-			2,686	-4		-		2,686
			Government		-		2,890	-4		-			2,890			249	-5		9,050	-4		-		9,299
			Asset-backed		-		5	-4		-			5			-			146	-4		-		146
		Real estate funds			-		-			-			-			-			-			57	-6	57
		Cash			-		131	-7		-			131			25			31	-8		-		56
	Total at fair value				-		12,342			562			12,904			503			18,973			592		20,068
		Insurance contracts
			at contract value										11											27
	Total plan assets												12,915											20,095
	(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
	(2) For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
	(3) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
	(4) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
	(5) For corporate and government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
	(6) For real estate funds, fair value is based on appraised values developed using comparable market transactions.
	(7) For cash balances held in the form of short-term fund units that are redeemable at the measurement date, the fair value is treated as a Level 2 input.
	(8) For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.
				U.S. Pension											Non-U.S. Pension
				Fair Value Measurement											Fair Value Measurement
				at December 31, 2013, Using:											at December 31, 2013, Using:
					Quoted											Quoted
					Prices											Prices
					in Active	Significant										in Active		Significant
				Markets for			Other		Significant						Markets for				Other		Significant
					Identical	Observable			Unobservable							Identical		Observable			Unobservable
					Assets		Inputs			Inputs						Assets			Inputs			Inputs
					(Level 1)		(Level 2)			(Level 3)			Total			(Level 1)			(Level 2)			(Level 3)		Total
				(millions of dollars)
	Asset category:
		Equity securities
			U.S.		-		2,514	-1		-			2,514			-			3,046	-1		-		3,046
			Non-U.S.		-		2,622	-1		-			2,622			294	-2		5,608	-1		-		5,902
		Private equity			-		-			523	-3		523			-			-			502	-3	502
		Debt securities
			Corporate		-		3,430	-4		-			3,430			-			2,125	-4		-		2,125
			Government		-		2,056	-4		-			2,056			272	-5		7,100	-4		-		7,372
			Asset-backed		-		6	-4		-			6			-			103	-4		-		103
		Real estate funds			-		-			-			-			-			-			136	-6	136
		Cash			-		27	-7		-			27			57			20	-8		-		77
	Total at fair value				-		10,655			523			11,178			623			18,002			638		19,263
		Insurance contracts
			at contract value										12											20
	Total plan assets												11,190											19,283
	(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
	(2) For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
	(3) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
	(4) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
(5) For corporate and government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
(6) For real estate funds, fair value is based on appraised values developed using comparable market transactions.
(7) For cash balances held in the form of short-term fund units that are redeemable at the measurement date, the fair value is treated as a Level 2 input.
(8) For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.
Fair Value Of The Benefit Plan Assets (Other Postretirement)				Other Postretirement
					Fair Value Measurement
				at December 31, 2014, Using:
					Quoted
					Prices
					in Active			Significant
					Markets for			Other			Significant
					Identical			Observable			Unobservable
					Assets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)			Total
					(millions of dollars)
	Asset category:
		Equity securities
			U.S.		-			106	-1		-			106
			Non-U.S.		-			75	-1		-			75
		Private equity			-			-			2	-2		2
		Debt securities
			Corporate		-			103	-3		-			103
			Government		-			171	-3		-			171
			Asset-backed		-			9	-3		-			9
		Cash			-			2			-			2
	Total at fair value				-			466			2			468
	For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
	For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
	For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
				Other Postretirement
				Fair Value Measurement
				at December 31, 2013, Using:
					Quoted
					Prices
					in Active			Significant
					Markets for			Other			Significant
					Identical			Observable			Unobservable
					Assets			Inputs			Inputs
					(Level 1)			(Level 2)			(Level 3)			Total
				(millions of dollars)
	Asset category:
		Equity securities
			U.S.		-			157	-1		-			157
			Non-U.S.		-			149	-1		-			149
		Private equity			-			-			9	-2		9
		Debt securities
			Corporate		-			129	-3		-			129
			Government		-			168	-3		-			168
			Asset-backed		-			4	-3		-			4
		Cash			-			4			-			4
	Total at fair value				-			611			9			620
	(1) For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
	(2) For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
	(3) For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
Change In Fair Value Of Level 3 Assets			2014
			Pension									Other
			U.S.				Non-U.S.					Postretirement
			Private				Private		Real			Private
			Equity				Equity		Estate			Equity
			(millions of dollars)
	Fair value at January 1		523				502		136			9
	Net realized gains/(losses)		2				23		-17			-
	Net unrealized gains/(losses)		89				31		8			-
	Net purchases/(sales)		-52				-21		-70			-7
	Fair value at December 31		562				535		57			2
			2013
			Pension									Other
			U.S.				Non-U.S.					Postretirement
			Private				Private		Real			Private
			Equity				Equity		Estate			Equity
			(millions of dollars)
	Fair value at January 1		489				448		293			7
	Net realized gains/(losses)		-1				11		-13			-
	Net unrealized gains/(losses)		86				57		10			3
	Net purchases/(sales)		-51				-14		-154			-1
	Fair value at December 31		523				502		136			9
Pension Plans With Accumulated Benefit Obligation In Excess Of Plan Assets			Pension Benefits
			U.S.					Non-U.S.
				2014		2013			2014		2013
			(millions of dollars)
	For funded pension plans with an accumulated benefit obligation
		in excess of plan assets:
		Projected benefit obligation		17,505		14,737			5,031		891
		Accumulated benefit obligation		14,493		12,342			4,590		689
		Fair value of plan assets		12,915		11,189			3,890		611
	For unfunded pension plans:
		Projected benefit obligation		3,024		2,567			7,839		7,133
		Accumulated benefit obligation		1,892		1,647			6,573		6,070
Estimated Next Year Amortization								Other
			Pension Benefits					Postretirement
			U.S.			Non-U.S.		Benefits
			(millions of dollars)
	Estimated 2015 amortization from accumulated other comprehensive income:
		Net actuarial loss/(gain) (1)		1,001		753			211
		Prior service cost (2)		6		105			14
	(1) The Corporation amortizes the net balance of actuarial losses/(gains) as a component of net periodic benefit cost over the average remaining service period of active plan participants.
	(2) The Corporation amortizes prior service cost on a straight-line basis as permitted under authoritative guidance for defined benefit pension and other postretirement benefit plans.
Expected Contributions and Benefit Payments for Pension Benefits And Other Postretirement Benefits				Pension Benefits				Other Postretirement Benefits
										Medicare
				U.S.		Non-U.S.		Gross		Subsidy Receipt
				(millions of dollars)
	Contributions expected in 2015			-		560		-			-
	Benefit payments expected in:
		2015		1,628		1,194		467			24
		2016		1,554		1,213		479			25
		2017		1,529		1,278		490			26
		2018		1,445		1,298		499			28
		2019		1,410		1,339		507			29
		2020 - 2024		6,714		6,988		2,613			172

Disclosures_About_Segments_And1

Disclosures About Segments And Related Information (Tables)	12 Months Ended
	Dec. 31, 2014
Disclosures About Segments And Related Information [Abstract]
Disclosures About Segments And Related Information															Corporate
		Upstream					Downstream				Chemical					and	Corporate
		U.S.		Non-U.S.			U.S.		Non-U.S.		U.S.		Non-U.S.		Financing			Total
			(millions of dollars)
	As of December 31, 2014
	Earnings after income tax		5,197		22,351			1,618		1,427		2,804		1,511		-2,388		32,520
	Earnings of equity companies included above		1,235		10,859			29		82		186		1,377		-445		13,323
	Sales and other operating revenue (1)		14,826		22,336			118,771		199,976		15,115		23,063		18		394,105
	Intersegment revenue		7,723		38,846			17,281		44,231		10,117		8,098		274		-
	Depreciation and depletion expense		5,139		8,523			654		1,228		370		645		738		17,297
	Interest revenue		-		-			-		-		-		-		75		75
	Interest expense		40		17			6		4		-		-		219		286
	Income taxes		1,300		15,165			610		968		1,032		358		-1,418		18,015
	Additions to property, plant and equipment		9,098		19,225			1,050		1,356		1,564		564		1,399		34,256
	Investments in equity companies		5,089		10,877			69		1,006		258		3,026		-308		20,017
	Total assets		92,555		161,033			18,371		33,299		8,798		18,449		16,988		349,493
	As of December 31, 2013
	Earnings after income tax		4,191		22,650			2,199		1,250		2,755		1,073		-1,538		32,580
	Earnings of equity companies included above		1,576		11,627			-460		22		189		1,422		-449		13,927
	Sales and other operating revenue (1)		13,712		25,349			123,802		218,904		15,295		23,753		21		420,836
	Intersegment revenue		8,343		45,761			20,781		52,624		11,993		8,232		285		-
	Depreciation and depletion expense		5,170		8,277			633		1,390		378		632		702		17,182
	Interest revenue		-		-			-		-		-		-		87		87
	Interest expense		30		26			7		8		1		-		-63		9
	Income taxes		2,197		21,554			721		481		989		363		-2,042		24,263
	Additions to property, plant and equipment		7,480		26,075			616		1,072		840		272		1,386		37,741
	Investments in equity companies		4,975		9,740			62		1,749		217		3,103		-227		19,619
	Total assets		88,698		157,465			19,261		40,661		7,816		19,659		13,248		346,808
	As of December 31, 2012
	Earnings after income tax		3,925		25,970			3,575		9,615		2,220		1,678		-2,103		44,880
	Earnings of equity companies included above		1,759		11,900			6		387		183		1,267		-492		15,010
	Sales and other operating revenue (1)		11,039		27,673			125,088		248,959		14,723		24,003		24		451,509
	Intersegment revenue		8,764		47,507			20,963		62,130		12,409		9,750		258		-
	Depreciation and depletion expense		5,104		7,340			594		1,280		376		508		686		15,888
	Interest revenue		-		-			-		-		-		-		117		117
	Interest expense		37		13			3		36		-		-1		239		327
	Income taxes		2,025		25,362			1,811		1,892		755		232		-1,032		31,045
	Additions to property, plant and equipment		9,697		21,769			480		1,153		338		659		1,083		35,179
	Investments in equity companies		4,020		9,147			195		2,069		233		3,143		-277		18,530
	Total assets		86,146		140,848			18,451		40,956		7,238		18,886		21,270		333,795
	(1) Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
Geographic Sales And Other Operating Revenue	Geographic
	Sales and other operating revenue (1)			2014		2013		2012
				(millions of dollars)
	United States			148,713		152,820		150,865
	Non-U.S.			245,392		268,016		300,644
		Total		394,105		420,836		451,509
	Significant non-U.S. revenue sources include:
		Canada		36,072		35,924		34,325
		United Kingdom		31,346		34,061		33,600
		Belgium		20,953		20,973		23,567
		Italy		18,880		19,273		18,228
		France		17,639		18,444		19,601
		Singapore		15,407		15,623		14,606
		Germany		14,816		15,701		15,871
	(1) Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
Schedule Of Long-Lived Assets By Geographic Regions	Long-lived assets			2014		2013		2012
				(millions of dollars)
	United States			104,000		98,271		94,336
	Non-U.S.			148,668		145,379		132,613
		Total		252,668		243,650		226,949
	Significant non-U.S. long-lived assets include:
		Canada		43,858		41,522		31,979
		Australia		15,328		14,258		13,415
		Nigeria		12,265		12,343		12,216
		Singapore		9,620		9,570		9,700
		Kazakhstan		9,138		8,530		7,785
		Angola		9,057		8,262		8,238
		Papua New Guinea		6,099		5,768		4,599
		Norway		5,139		6,542		7,040

Income_SalesBased_And_Other_Ta1

Income, Sales-Based And Other Taxes (Tables)	12 Months Ended
	Dec. 31, 2014
Income, Sales-Based And Other Taxes [Abstract]
Schedule Of Income, Sales-Based And Other Taxes								2014					2013				2012
						U.S.	Non-U.S.			Total	U.S.	Non-U.S.		Total	U.S.	Non-U.S.		Total
											(millions of dollars)
	Income tax expense
		Federal and non-U.S.
			Current			1,456		14,755		16,211	1,073		22,115	23,188	1,791		25,650	27,441
			Deferred - net			900		1,398		2,298	-116		757	641	1,097		1,816	2,913
		U.S. tax on non-U.S. operations				5		-		5	37		-	37	89		-	89
				Total federal and non-U.S.		2,361		16,153		18,514	994		22,872	23,866	2,977		27,466	30,443
		State (1)				-499		-		-499	397		-	397	602		-	602
				Total income tax expense		1,862		16,153		18,015	1,391		22,872	24,263	3,579		27,466	31,045
	Sales-based taxes					6,310		23,032		29,342	5,992		24,597	30,589	5,785		26,624	32,409
	All other taxes and duties
		Other taxes and duties				378		31,908		32,286	955		32,275	33,230	1,406		34,152	35,558
		Included in production and
			manufacturing expenses			1,454		1,179		2,633	1,318		1,182	2,500	1,242		1,308	2,550
		Included in SG&A expenses				155		441		596	150		516	666	154		595	749
			Total other taxes and duties			1,987		33,528		35,515	2,423		33,973	36,396	2,802		36,055	38,857
				Total		10,159		72,713		82,872	9,806		81,442	91,248	12,166		90,145	102,311
	(1) In 2014, state taxes included a favorable adjustment of deferred taxes of approximately $830 million.
Reconciliation Between Income Tax Expense And A Theoretical U.S. Tax					2014		2013		2012
					(millions of dollars)
	Income before income taxes
		United States			9,080		9,746		11,222
		Non-U.S.			42,550		47,965		67,504
			Total		51,630		57,711		78,726
	Theoretical tax				18,071		20,199		27,554
	Effect of equity method of accounting				-4,663		-4,874		-5,254
	Non-U.S. taxes in excess of theoretical U.S. tax				5,442		10,528		8,434
	U.S. tax on non-U.S. operations				5		37		89
	State taxes, net of federal tax benefit				-324		258		391
	Other				-516		-1,885		-169
			Total income tax expense		18,015		24,263		31,045
	Effective tax rate calculation
	Income taxes				18,015		24,263		31,045
	ExxonMobil share of equity company income taxes				5,678		6,061		5,859
			Total income taxes		23,693		30,324		36,904
	Net income including noncontrolling interests				33,615		33,448		47,681
			Total income before taxes		57,308		63,772		84,585
	Effective income tax rate				41%		48%		44%
Deferred Tax Liabilities/(Assets)	Tax effects of temporary differences for:			2014		2013
				(millions of dollars)
	Property, plant and equipment			51,643		50,884
	Other liabilities			4,359		3,474
		Total deferred tax liabilities		56,002		54,358
	Pension and other postretirement benefits			-8,140		-6,573
	Asset retirement obligations			-6,162		-6,083
	Tax loss carryforwards			-4,099		-3,393
	Other assets			-6,446		-6,246
		Total deferred tax assets		-24,847		-22,295
	Asset valuation allowances			2,570		2,491
		Net deferred tax liabilities		33,725		34,554
Deferred Income Tax (Assets) And Liabilities By Balance Sheet Classification	Balance sheet classification			2014		2013
				(millions of dollars)
	Other current assets			-2,001		-3,575
	Other assets, including intangibles, net			-3,955		-2,822
	Accounts payable and accrued liabilities			451		421
	Deferred income tax liabilities			39,230		40,530
		Net deferred tax liabilities		33,725		34,554
Unrecognized Tax Benefits	Gross unrecognized tax benefits		2014		2013		2012
			(millions of dollars)
	Balance at January 1		7,838		7,663		4,922
		Additions based on current year's tax positions	1,454		1,460		1,662
		Additions for prior years' tax positions	448		464		2,559
		Reductions for prior years' tax positions	-532		-249		-535
		Reductions due to lapse of the statute of limitations	-117		-588		-79
		Settlements with tax authorities	-43		-849		-855
		Foreign exchange effects/other	-62		-63		-11
	Balance at December 31		8,986		7,838		7,663
Remaining Tax Years Subject To Examination By Major Tax Jurisdiction		Country of Operation	Open Tax Years
		Abu Dhabi	2012 - 2014
		Angola	2009 - 2014
		Australia:	2000 - 2003
			2005
			2008 - 2014
		Canada	2007 - 2014
		Equatorial Guinea	2007 - 2014
		Malaysia	2008 - 2014
		Nigeria	2004 - 2014
		Norway	2005 - 2014
		Qatar	2008 - 2014
		Russia	2011 - 2014
		United Kingdom	2010 - 2014
		United States	2006 - 2014

Miscellaneous_Financial_Inform2

Miscellaneous Financial Information (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Miscellaneous Financial Information [Abstract]
Research and development expense	$971,000,000	$1,044,000,000	$1,042,000,000
Foreign currency transaction gain/(loss), before tax	-225,000,000	155,000,000	159,000,000
Gains on combined effects of LIFO inventory accumulations and draw-downs	187,000,000	282,000,000	328,000,000
Replacement cost of inventories estimated to exceed LIFO carrying values	$10,600,000,000	$21,200,000,000

Miscellaneous_Financial_Inform3

Miscellaneous Financial Information (Crude Oil, Products And Merchandise) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Miscellaneous Financial Information [Abstract]
Petroleum products	$4,100,000,000	$3,900,000,000
Crude oil	4,600,000,000	4,700,000,000
Chemical products	2,900,000,000	2,900,000,000
Gas / other	800,000,000	600,000,000
Total	$12,384,000,000	$12,117,000,000

Other_Comprehensive_Income_Inf2

Other Comprehensive Income Information (Schedule of Accumulated Other Comprehensive Income Information) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Current period change excluding amounts reclassified from accumulated other comprehensive income, Cumulative Foreign Exchange Translation Adjustment	($5,847)	($3,620)	$920
Amounts reclassified from accumulated other comprehensive income, Cumulative Foreign Exchange Translation Adjustment	152	-23	-4,352
Current period change excluding amounts reclassified from accumulated other comprehensive income, Postretirement Benefits Reserves Adjustment	-4,262	3,174	-3,574
Amounts reclassified from accumulated other comprehensive income, Postretirement Benefits Reserves Adjustment	1,111	1,820	2,395
Current period change excluding amounts reclassified from accumulated other comprehensive income, Unrealized Change in Stock Investments	-63
Amounts reclassified from accumulated other comprehensive income, Unrealized Change in Stock Investments	3
Beginning Balance, Total	-10,725
Total other comprehensive income	-8,906	1,351	-4,611
Ending Balance, Total	-18,957	-10,725
Exxon Mobil Corporation Share After Noncontrolling Interest [Member]
Beginning Balance, Cumulative Foreign Exchange Translation Adjustment	-846	2,410	4,168
Current period change excluding amounts reclassified from accumulated other comprehensive income, Cumulative Foreign Exchange Translation Adjustment	-5,258	-3,233	842
Amounts reclassified from accumulated other comprehensive income, Cumulative Foreign Exchange Translation Adjustment	152	-23	-2,600
Total change in accumulated other comprehensive income, Cumulative Foreign Exchange Translation Adjustment	-5,106	-3,256	-1,758
Ending Balance, Cumulative Foreign Exchange Translation Adjustment	-5,952	-846	2,410
Beginning Balance, Postretirement Benefits Reserves Adjustment	-9,879	-14,594	-13,291
Current period change excluding amounts reclassified from accumulated other comprehensive income, Postretirement Benefits Reserves Adjustment	-4,132	2,963	-3,402
Amounts reclassified from accumulated other comprehensive income, Postretirement Benefits Reserves Adjustment	1,066	1,752	2,099
Total change in accumulated other comprehensive income, Postretirement Benefits Reserves Adjustment	-3,066	4,715	-1,303
Ending Balance, Postretirement Benefits Reserves Adjustment	-12,945	-9,879	-14,594
Current period change excluding amounts reclassified from accumulated other comprehensive income, Unrealized Change in Stock Investments	-63
Amounts reclassified from accumulated other comprehensive income, Unrealized Change in Stock Investments	3
Total change in accumulated other comprehensive income, Unrealized Change in Stock Investments	-60
Ending Balance, Unrealized Change in Stock Investments	-60
Beginning Balance, Total	-10,725	-12,184	-9,123
Current period change excluding amounts reclassified from accumulated other comprehensive income, Total	-9,453	-270	-2,560
Amounts reclassified from accumulated other comprehensive income, Total	1,221	1,729	-501
Total other comprehensive income	-8,232	1,459	-3,061
Ending Balance, Total	($18,957)	($10,725)	($12,184)

Other_Comprehensive_Income_Inf3

Other Comprehensive Income Information (Amounts Reclassified Out Of Acc Other Comp Income) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Accumulated Foreign Exchange Translation Adjustment [Member]
Foreign exchange translation gain/(loss) included in net income (Statement of Income line: Other Income)	($152)		$23		$4,352
Accumulated Defined Benefit Plans Adjustment [Member]
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	-1,571	[1]	-2,616	[1]	-3,621	[1]
Accumulated Net Unrealized Investment Gain Loss [Member]
Realized change in fair value of stock investments included in net income (Statement of Income line: Other income)	($5)
[1]	These accumulated other comprehensive income components are included in the computation of net periodic pension cost. (See Note 17 b Pension and Other Postretirement Benefits for additional details.)

Other_Comprehensive_Income_Inf4

Other Comprehensive Income Information (Schedule Of Income Tax (Expense)/Credit For Components Of Other Comprehensive Income) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Other Comprehensive Income Information Tax [Abstract]
Foreign exchange translation adjustment	$292	$218	($236)
Postretirement benefits reserves adjustment (excluding amortization)	2,009	-1,540	1,619
Amortization and settlement of postretirement benefits reserves adjustment included in net periodic benefit costs	-460	-796	-1,226
Unrealized change in fair value of stock investments	34
Realized change in fair value of stock investments included in net income	-2
Total	$1,873	($2,118)	$157

Cash_Flow_Information_Cash_Pay

Cash Flow Information (Cash Payments For Interest And Income Taxes) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flow Information [Abstract]
Cash payments for interest	$380	$426	$555
Cash payments for income taxes	18,085	25,066	24,349
Asset exchanges, primarily noncash	$1,200		$1,000

Additional_Working_Capital_Inf2

Additional Working Capital Information (Narrative) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Line Of Credit Facility [Line Items]
Weighted-average interest rate on short-term borrowings outstanding	0.30%	0.40%
Short Term Financing [Member]
Line Of Credit Facility [Line Items]
Unused credit lines	6,300

Additional_Working_Capital_Inf3

Additional Working Capital Information (Schedule Of Notes, Accounts Receivable And Payable, Loans Payable, Accrued Liabilities) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Additional Working Capital Information [Abstract]
Trade notes and accounts receivable, less reserves of $113 million and $112 million	$18,541	$25,993
Other notes and accounts receivable, less reserves of $48 million and $28 million	9,468	7,159
Total notes and accounts receivable	28,009	33,152
Bank loans	473	723
Commercial paper	16,225	14,051
Long-term debt due within one year	770	1,034
Total notes and loans payable	17,468	15,808
Trade payables	25,286	30,920
Payables to equity companies	6,589	6,587
Accrued taxes other than income taxes	3,290	3,883
Other accounts payable and accrued liabilities	7,062	6,695
Total accounts payable and accrued liabilities	42,227	48,085
Trade notes and accounts receivable, reserves	113	112
Other notes and accounts receivable, reserves	$48	$28

Equity_Company_Information_Nar

Equity Company Information (Narrative) (Details) (USD $)	12 Months Ended
In Billions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Equity Method Investments [Line Items]
Share of equity company sales revenues from sales to consolidated companies	14.00%	13.00%	16.00%
Rosneft VIE Joint Venture [Member]
Schedule of Equity Method Investments [Line Items]
Maximum Exposure to Loss from Rosneft JV's	1

Equity_Company_Information_Sch

Equity Company Information (Schedule Of Equity Company Financial Summary) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Subsidiary or Equity Method Investee [Line Items]
Net assets	$20,017	$19,619	$18,530
ExxonMobil Share Of Equity [Member]
Subsidiary or Equity Method Investee [Line Items]
Total revenues	55,855	68,084	67,572
Income before income taxes	19,014	19,999	20,882
Income taxes	5,684	6,069	5,868
Income from equity affiliates	13,330	13,930	15,014
Current assets	16,802	19,545	18,483
Long-term assets	33,619	35,695	33,798
Total assets	50,421	55,240	52,281
Current liabilities	11,472	15,243	14,265
Long-term liabilities	19,470	20,873	19,715
Net assets	19,479	19,124	18,301
Total Equity Company Including All Owners [Member]
Subsidiary or Equity Method Investee [Line Items]
Total revenues	183,708	236,161	224,953
Income before income taxes	65,549	69,454	69,411
Income taxes	20,520	21,618	20,703
Income from equity affiliates	45,029	47,836	48,708
Current assets	49,905	62,398	59,612
Long-term assets	110,754	116,450	111,131
Total assets	160,659	178,848	170,743
Current liabilities	37,333	54,550	49,698
Long-term liabilities	66,231	68,857	68,855
Net assets	$57,095	$55,441	$52,190

Equity_Company_Information_Sch1

Equity Company Information (Schedule Of The Corporation's Percentage Ownership Interest) (Details)	Dec. 31, 2014
Upstream [Member] | Aera Energy LLC [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	48.00%
Upstream [Member] | BEB Erdgas und Erdoel GmbH & Co. KG [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Upstream [Member] | Cameroon Oil Transportation Company S.A. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	41.00%
Upstream [Member] | Cross Timbers Energy, LLC [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Upstream [Member] | Golden Pass LNG Terminal LLC [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	18.00%
Upstream [Member] | Karmorneftegaz Holding SARL [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	33.00%
Upstream [Member] | Marine Well Containment Company LLC [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	10.00%
Upstream [Member] | Nederlandse Aardolie Maatschappij B.V. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Upstream [Member] | Qatar Liquefied Gas Company Limited [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	10.00%
Upstream [Member] | Qatar Liquefied Gas Company Limited (2) [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	24.00%
Upstream [Member] | Ras Laffan Liquefied Natural Gas Company Limited [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	25.00%
Upstream [Member] | Ras Laffan Liquefied Natural Gas Company Limited (II) [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	31.00%
Upstream [Member] | Ras Laffan Liquefied Natural Gas Company Limited (3) [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	30.00%
Upstream [Member] | South Hook LNG Terminal Company Limited [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	24.00%
Upstream [Member] | Tengizchevroil, LLP [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	25.00%
Upstream [Member] | Terminale GNL Adriatico S.r.l. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	71.00%
Downstream [Member] | Chalmette Refining, LLC [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Downstream [Member] | Fujian Refining & Petrochemical Co. Ltd. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	25.00%
Downstream [Member] | Saudi Aramco Mobil Refinery Company Ltd. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Chemical [Member] | Al-Jubail Petrochemical Company [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Chemical [Member] | Infineum Holdings B.V. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Chemical [Member] | Infineum USA L.P. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%
Chemical [Member] | Saudi Yanbu Petrochemical Co. [Member]
Subsidiary or Equity Method Investee [Line Items]
Percentage Ownership Interest	50.00%

Investments_Advances_And_LongT2

Investments, Advances And Long-Term Receivables (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Investments, Advances And Long-Term Receivables [Abstract]
Investments (Companies carried at equity in underlying assets)	$20,017	$19,619	$18,530
Advances (Companies carried at equity in underlying assets)	9,818	10,476
Total equity company investments and advances	29,835	30,095
Companies carried at cost or less and stock investments carried at fair value	526	115
Long-term receivables and miscellaneous investments at cost or less, net of reserves of $2,662 million and $2,938 million	4,878	6,118
Total	35,239	36,328
Reserves for long-term receivables and miscellaneous investments	$2,662	$2,938

Property_Plant_And_Equipment_A2

Property, Plant And Equipment And Asset Retirement Obligations (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Property, Plant and Equipment [Line Items]
Accumulated depreciation and depletion	$194,121	$190,867
Interest capitalized	$344	$309	$506
Downstream [Member] | Refinery And Lubes Basestock Manufacturing Facilities [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of equipment, years	25 years 0 months 0 days
Downstream [Member] | Service Station Buildings And Fixed Improvements [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of equipment, years	20 years 0 months 0 days
Chemical [Member] | Investments In Process Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful life of equipment, years	20 years 0 months 0 days

Property_Plant_And_Equipment_A3

Property, Plant And Equipment And Asset Retirement Obligations (Property, Plant And Equipment) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Cost	$446,789	$434,517
Property, Plant and Equipment, Net	252,668	243,650	226,949
Upstream [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Cost	347,170	336,359
Property, Plant and Equipment, Net	205,308	197,554
Downstream [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Cost	53,327	54,456
Property, Plant and Equipment, Net	22,639	23,219
Chemical [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Cost	30,717	29,487
Property, Plant and Equipment, Net	14,918	13,965
Other [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Cost	15,575	14,215
Property, Plant and Equipment, Net	$9,803	$8,912

Property_Plant_And_Equipment_A4

Property, Plant And Equipment And Asset Retirement Obligations (Asset Retirement Obligations) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Property, Plant And Equipment And Asset Retirement Obligations [Abstract]
Beginning balance	$12,988	$11,973
Accretion expense and other provisions	871	785
Reduction due to property sales	-151	-97
Payments made	-724	-664
Liabilities incurred	122	603
Foreign currency translation	-908	-344
Revisions	1,226	732
Ending balance	$13,424	$12,988

Accounting_For_Suspended_Explo2

Accounting For Suspended Exploratory Well Costs (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Exploratory Wells Drilled [Line Items]
Number of projects that have exploratory well costs capitalized for a period greater than twelve months as of December 31, 2014	53	50	45
Number of projects that have drilling in the preceding twelve months or exploratory activity planned in the next two years as of December 31, 2014	15
Number of projects with completed exploratory activity progressing toward development as of December 31, 2014	38
Capitalized exploratory well costs	$3,587	$2,707	$2,679	$2,881
Total 38 Projects [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	$1,035

Accounting_For_Suspended_Explo3

Accounting For Suspended Exploratory Well Costs (Change In Capitalized Suspended Exploratory Well Costs) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting For Suspended Exploratory Well Costs [Abstract]
Capitalized suspended exploratory well costs, beginning balance	$2,707	$2,679	$2,881
Additions pending the determination of proved reserves	1,095	293	868
Charged to expense	-28	-52	-95
Reclassifications to wells, facilities and equipment based on the determination of proved reserves	-160	-107	-631
Divestments/Other	-27	-106	-344
Capitalized suspended exploratory well costs, ending balance	3,587	2,707	2,679
Ending balance attributed to equity companies included above	$645	$13	$3

Accounting_For_Suspended_Explo4

Accounting For Suspended Exploratory Well Costs (Schedule Of Period End Capitalized Suspended Exploratory Well Costs) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Millions, unless otherwise specified
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Capitalized for a period of one year or less	$1,095	$293	$866
Capitalized suspended exploratory well costs, total	3,587	2,707	2,679	2,881
Capitalized For A Period Of Between One And Five Years [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Capitalized suspended exploratory well costs	1,659	1,705	1,176
Capitalized For A Period Of Between Five And Ten Years [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Capitalized suspended exploratory well costs	544	470	401
Capitalized For A Period Of Greater Than Ten Years [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Capitalized suspended exploratory well costs	289	239	236
Capitalized For A Period Greater Than One Year [Member]
Projects with Exploratory Well Costs Capitalized for More than One Year [Line Items]
Capitalized suspended exploratory well costs	$2,492	$2,414	$1,813

Accounting_For_Suspended_Explo5

Accounting For Suspended Exploratory Well Costs (Schedule Of Number Of Projects With Suspended Exploratory Well Costs) (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting For Suspended Exploratory Well Costs [Abstract]
Number of projects with first capitalized well drilled in the preceding 12 months	8	8	10
Number of projects that have exploratory well costs capitalized for a period of greater than 12 months	53	50	45
Total	61	58	55

Accounting_For_Suspended_Explo6

Accounting For Suspended Exploratory Well Costs (Schedule Of Additional Detail For The Projects) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	3,587	$2,707	$2,679	$2,881
Total 38 Projects [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	1,035
Angola [Member] | Project In Angola - Kaombo Split Hub Phase 2[Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	20
Angola [Member] | Project In Angola - Kaombo Split Hub Phase 2[Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2005
Angola [Member] | Project In Angola - Kaombo Split Hub Phase 2[Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2006
Angola [Member] | Project In Angola - Perpetua-Zinia- Acacia [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	15
Angola [Member] | Project In Angola - Perpetua-Zinia- Acacia [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Angola [Member] | Project In Angola - Perpetua-Zinia- Acacia [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
Australia [Member] | Project In Australia - East Pilchard [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	8
Australia [Member] | Project In Australia - East Pilchard [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2001
Australia [Member] | Project In Australia - East Pilchard [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2001
Australia [Member] | Project In Australia - SE Longtom [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	12
Australia [Member] | Project In Australia - SE Longtom [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Australia [Member] | Project In Australia - SE Longtom [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Australia [Member] | Project in Australia - SE Remora [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	38
Australia [Member] | Project in Australia - SE Remora [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Australia [Member] | Project in Australia - SE Remora [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Indonesia [Member] | Project In Indonesia - Alas Tua West [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	16
Indonesia [Member] | Project In Indonesia - Alas Tua West [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Indonesia [Member] | Project In Indonesia - Alas Tua West [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Indonesia [Member] | Project In Indonesia - Cepu Gas [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	28
Indonesia [Member] | Project In Indonesia - Cepu Gas [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Indonesia [Member] | Project In Indonesia - Cepu Gas [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2011
Indonesia [Member] | Project in Indonesia - Kedung Keris [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	11
Indonesia [Member] | Project in Indonesia - Kedung Keris [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2011
Indonesia [Member] | Project in Indonesia - Kedung Keris [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2011
Indonesia [Member] | Project In Indonesia - Natuna [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	118
Indonesia [Member] | Project In Indonesia - Natuna [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1981
Indonesia [Member] | Project In Indonesia - Natuna [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1983
Kazakhstan [Member] | Project In Kazakhstan - Kairan [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	53
Kazakhstan [Member] | Project In Kazakhstan - Kairan [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2004
Kazakhstan [Member] | Project In Kazakhstan - Kairan [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2007
Malaysia [Member] | Project In Malaysia - Besar [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	18
Malaysia [Member] | Project In Malaysia - Besar [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1992
Malaysia [Member] | Project In Malaysia - Besar [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
Malaysia [Member] | Project in Malaysia - Bindu [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	2
Malaysia [Member] | Project in Malaysia - Bindu [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1995
Malaysia [Member] | Project in Malaysia - Bindu [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1995
Nigeria [Member] | Project In Nigeria - Bolia [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	15
Nigeria [Member] | Project In Nigeria - Bolia [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2002
Nigeria [Member] | Project In Nigeria - Bolia [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2006
Nigeria [Member] | Project In Nigeria - Bosi [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	79
Nigeria [Member] | Project In Nigeria - Bosi [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2002
Nigeria [Member] | Project In Nigeria - Bosi [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2006
Nigeria [Member] | Project in Nigeria - Bosi Central [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	16
Nigeria [Member] | Project in Nigeria - Bosi Central [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2006
Nigeria [Member] | Project in Nigeria - Bosi Central [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2006
Nigeria [Member] | Project in Nigeria - Erha Northeast [Member}
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	26
Nigeria [Member] | Project in Nigeria - Erha Northeast [Member} | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Nigeria [Member] | Project in Nigeria - Erha Northeast [Member} | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Nigeria [Member] | Project In Nigeria - Owowo [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	50
Nigeria [Member] | Project In Nigeria - Owowo [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
Nigeria [Member] | Project In Nigeria - Owowo [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2012
Nigeria [Member] | Project In Nigeria - Pegi [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	32
Nigeria [Member] | Project In Nigeria - Pegi [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
Nigeria [Member] | Project In Nigeria - Pegi [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
Nigeria [Member] | Project in Nigeria - Satellite Field Development Phase 2 [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	12
Nigeria [Member] | Project in Nigeria - Satellite Field Development Phase 2 [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2013
Nigeria [Member] | Project in Nigeria - Satellite Field Development Phase 2 [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2013
Nigeria [Member] | Other 4 Projects In Nigeria [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	14
Nigeria [Member] | Other 4 Projects In Nigeria [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2002
Nigeria [Member] | Other 4 Projects In Nigeria [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2002
Norway [Member] | Project in Norway - Gamma [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	15
Norway [Member] | Project in Norway - Gamma [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Norway [Member] | Project in Norway - Gamma [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
Norway [Member] | Project In Norway - Lavrans [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	18
Norway [Member] | Project In Norway - Lavrans [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1995
Norway [Member] | Project In Norway - Lavrans [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	1999
Norway [Member] | Other 7 Projects In Norway [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	29
Norway [Member] | Other 7 Projects In Norway [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2008
Norway [Member] | Other 7 Projects In Norway [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2013
Papua New Guinea [Member] | Project In Papua New Guinea - Juha [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	28
Papua New Guinea [Member] | Project In Papua New Guinea - Juha [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2007
Papua New Guinea [Member] | Project In Papua New Guinea - Juha [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2007
Papua New Guinea [Member] | Project in Papua New Guinea - P'nyang [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	58
Papua New Guinea [Member] | Project in Papua New Guinea - P'nyang [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2012
Papua New Guinea [Member] | Project in Papua New Guinea - P'nyang [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2012
Republic of Congo [Member] | Project In Republic of Congo - Mer Tres Profonde Sud [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	56
Republic of Congo [Member] | Project In Republic of Congo - Mer Tres Profonde Sud [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2000
Republic of Congo [Member] | Project In Republic of Congo - Mer Tres Profonde Sud [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2007
United Kingdom [Member] | Project In United Kingdom - Phyllis [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	8
United Kingdom [Member] | Project In United Kingdom - Phyllis [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2004
United Kingdom [Member] | Project In United Kingdom - Phyllis [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2004
United States [Member] | Project In United States - Hadrian North [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	209
United States [Member] | Project In United States - Hadrian North [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2010
United States [Member] | Project In United States - Hadrian North [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2013
United States [Member] | Project in United States - Tip Top [Member]
Exploratory Wells Drilled [Line Items]
Capitalized exploratory well costs	31
United States [Member] | Project in United States - Tip Top [Member] | Minimum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009
United States [Member] | Project in United States - Tip Top [Member] | Maximum [Member]
Exploratory Wells Drilled [Line Items]
Years wells drilled, period	2009

Leased_Facilities_Narrative_De

Leased Facilities (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Leased Facilities [Abstract]
Minimum undiscounted lease commitments	$6,213
Estimated related rental income from noncancelable subleases	$70

Leased_Facilities_Leased_Facil

Leased Facilities (Leased Facilities) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Leased Facilities [Abstract]
Lease Payments Under Minimum Commitments, 2015	$2,034
Lease Payments Under Minimum Commitments, 2016	1,379
Lease Payments Under Minimum Commitments, 2017	774
Lease Payments Under Minimum Commitments, 2018	418
Lease Payments Under Minimum Commitments, 2019	312
Lease Payments Under Minimum Commitments, 2020 and beyond	1,296
Lease Payments Under Minimum Commitments, Total	6,213
Related Sublease Rental Income, 2015	31
Related Sublease Rental Income, 2016	7
Related Sublease Rental Income, 2017	6
Related Sublease Rental Income, 2018	3
Related Sublease Rental Income, 2019	3
Related Sublease Rental Income, 2020 and beyond	20
Related Sublease Rental Income, Total	$70

Leased_Facilities_Net_Rental_C

Leased Facilities (Net Rental Cost) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Leased Facilities [Abstract]
Rental cost	$4,077	$3,841	$3,851
Less sublease rental income	52	44	44
Net rental cost	$4,025	$3,797	$3,807

Earnings_Per_Share_Details

Earnings Per Share (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Earnings per common share
Net income attributable to ExxonMobil	$32,520		$32,580		$44,880
Weighted average number of common shares outstanding	4,282		4,419		4,628
Earnings per common share (dollars)	$7.60	[1]	$7.37	[1]	$9.70	[1]
Dividends paid per common share (dollars)	$2.70		$2.46		$2.18
[1]	The earnings per common share and earnings per common share - assuming dilution are the same in each period shown.

Financial_Instruments_And_Deri1

Financial Instruments And Derivatives (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financial Instruments And Derivatives [Line Items]
Estimated fair value of total long-term debt, excluding capitalized lease obligations		$11,700	$6,800
Recorded book values of total long-term debt, excluding capitalized lease obligations		11,300	6,500
Derivative asset at fair value, net		75	1
Gain (loss) before-tax earnings impact of derivatives		110	-7	-23
Additions to long-term debt	5,500	5,731	345	995
Level 1 [Member]
Financial Instruments And Derivatives [Line Items]
Estimated fair value of total long-term debt, excluding capitalized lease obligations		11,036
Level 2 [Member]
Financial Instruments And Derivatives [Line Items]
Estimated fair value of total long-term debt, excluding capitalized lease obligations		561
Level 3 [Member]
Financial Instruments And Derivatives [Line Items]
Estimated fair value of total long-term debt, excluding capitalized lease obligations		$63

LongTerm_Debt_Narrative_Detail

Long-Term Debt (Narrative) (Details) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Schedule of Capitalization, Long-term Debt [Line Items]
Long-term debt due in U.S. dollars		$11,341
U.S. dollar equivalent at year-end exchange rates of amounts payable in foreign currencies		312
Portion of long-term debt included in current liability		770	1,034
Long-term debt maturing - 2016		537
Long-term debt maturing - 2017		2,993
Long-term debt maturing - 2018		872
Long-term debt maturing - 2019		2,353
Additions to long-term debt	5,500	5,731	345	995
Long Term Financing [Member]
Schedule of Capitalization, Long-term Debt [Line Items]
Unused credit lines		$500

LongTerm_Debt_Summarized_LongT

Long-Term Debt (Summarized Long-Term Debt) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Debt Instrument, Unamortized Premium	$219		$271
Long-term debt	11,653		6,891
Combined Exxon Mobil And Affiliates [Member] | Other U.S. Dollar Obligations [Member]
Other long-term debt	104	[1]	112	[1]
Average effective interest rate	4.20%		4.40%
Combined Exxon Mobil And Affiliates [Member] | Other Foreign Currency Obligations [Member]
Other long-term debt	9		9
0.921% Notes Due 2017 [Member] | Exxon Mobil Corporation [Member] | Other U.S. Dollar Obligations [Member]
Senior notes, noncurrent	1,500
Interest rate	0.92%
Debt maturity	15-Mar-17
Floating-Rate Notes Due 2017 [Member] | Exxon Mobil Corporation [Member] | Other U.S. Dollar Obligations [Member]
Senior notes, noncurrent	750	[2]
Debt maturity	15-Mar-17
Average effective interest rate	0.30%
1.819% Notes Due 2019 [Member] | Exxon Mobil Corporation [Member] | Other U.S. Dollar Obligations [Member]
Senior notes, noncurrent	1,750
Interest rate	1.82%
Debt maturity	15-Mar-19
Floating-Rate Notes Due 2019 [Member] | Exxon Mobil Corporation [Member] | Other U.S. Dollar Obligations [Member]
Senior notes, noncurrent	500	[3]
Debt maturity	15-Mar-19
Average effective interest rate	0.40%
3.176% Notes Due 2024 [Member] | Exxon Mobil Corporation [Member] | Other U.S. Dollar Obligations [Member]
Senior notes, noncurrent	1,000
Interest rate	3.18%
Debt maturity	15-Mar-24
5.000% Senior Notes Due 2015 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent			132
Interest rate			5.00%
Debt maturity			31-Jan-15
5.300% Senior Notes Due 2015 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent			243
Interest rate			5.30%
Debt maturity			30-Jun-15
5.650% Senior Notes Due 2016 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	207		212
Interest rate	5.65%
Debt maturity	1-Apr-16		1-Apr-16
6.250% Senior Notes Due 2017 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	477		489
Interest rate	6.25%
Debt maturity	1-Aug-17		1-Aug-17
5.500% Senior Notes Due 2018 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	383		389
Interest rate	5.50%
Debt maturity	15-Jun-18		15-Jun-18
6.500% Senior Notes Due 2018 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	474		485
Interest rate	6.50%
Debt maturity	15-Dec-18		15-Dec-18
6.100% Senior Notes Due 2036 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	199		200
Interest rate	6.10%
Debt maturity	1-Apr-36		1-Apr-36
6.750% Senior Notes Due 2037 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	309		312
Interest rate	6.75%
Debt maturity	1-Aug-37		1-Aug-37
6.375% Senior Notes Due 2038 [Member] | XTO Energy Inc. [Member]
Senior notes, noncurrent	236		238
Interest rate	6.38%
Debt maturity	15-Jun-38		15-Jun-38
Variable Notes Due 2015-2019 [Member] | Mobil Producing Nigeria Unlimited [Member]
Senior notes, noncurrent	399	[4]	742	[4]
Debt Instrument, maturity date range, start	15-Jun-16		31-Dec-17
Debt Instrument, maturity date range, end	15-Mar-19		31-Dec-19
Average effective interest rate	4.50%		4.60%
Variable Notes Due 2015-2019 [Member] | Esso (Thailand) Public Company Ltd. [Member]
Senior notes, noncurrent	121	[5]	177	[5]
Debt Instrument, maturity date range, start	30-Nov-17		28-Sep-15
Debt Instrument, maturity date range, end	31-Dec-19		30-Nov-17
Average effective interest rate	2.40%		3.30%
Debentures Due 2021 [Member] | Mobil Corporation [Member]
Other long-term debt	249		249
Interest rate	8.63%
Debt maturity	15-Aug-21		15-Aug-21
Industrial Revenue Bonds Due 2015-2051 [Member] | Combined Exxon Mobil And Affiliates [Member]
Other long-term debt	2,611	[6]	2,527	[6]
Debt Instrument, maturity date range, start	1-Apr-17		31-Jul-15
Debt Instrument, maturity date range, end	1-Dec-51		1-Dec-51
Average effective interest rate	0.03%		0.06%
Capitalized Lease Obligations [Member] | Combined Exxon Mobil And Affiliates [Member]
Average effective interest rate	7.00%		7.80%
Long-term debt	$375	[7]	$375	[7]
[1]	Average effective interest rate of 4.2% in 2014 and 4.4% in 2013.
[2]	Average effective interest rate of 0.3% in 2014.
[3]	Average effective interest rate of 0.4% in 2014.
[4]	Average effective interest rate of 4.5% in 2014 and 4.6% in 2013.
[5]	Average effective interest rate of 2.4% in 2014 and 3.3% in 2013.
[6]	Average effective interest rate of 0.03% in 2014 and 0.06% in 2013.
[7]	Average imputed interest rate of 7.0% in 2014 and 7.8% in 2013.

Incentive_Program_Narrative_De

Incentive Program (Narrative) (Details) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Minimum ownership of affiliates needed for awards	50.00%
Number of shares issuable under 2003 incentive program, maximum	220,000,000
Remaining shares available for award under 2003 incentive program	108,000,000
Options and stock appreciation rights grant, minimum percentage of market value, date of grant	100.00%
Maximum Life Per Program Member [Member]
Share-based compensation arrangement by share-based payment award expiration period	10 years 0 months 0 days
Restricted Stock [Member]
Long-term incentive awards	9,775,000	9,729,000	10,017,000
Unrecognized compensation cost	$2,339
Unrecognized compensation cost, weighted-average period of recognition, years	4 years 6 months 0 days
Compensation cost charged against income	831	854	854
Income tax benefit recognized in income	76	78	79
Fair value of shares/awards vested	946	1,040	926
Cash payments, vested restricted stock units	$73	$67	$66
Percent of the shares in each award vesting after three years	50.00%
Percent of the shares in each award vesting after seven years	50.00%
Percent of shares in each award vesting after five years	50.00%
Percent of shares in each award vesting in later of ten years or retirement	50.00%
Restricted Stock [Member] | Minimum [Member]
Vesting Period	3 years 0 months 0 days
Restricted Stock [Member] | Minimum [Member] | Executive Officer [Member]
Vesting Period	5 years 0 months 0 days
Restricted Stock [Member] | Maximum [Member]
Vesting Period	7 years 0 months 0 days
Restricted Stock [Member] | Maximum [Member] | Executive Officer [Member]
Vesting Period	10 years 0 months 0 days

Incentive_Program_Summary_Of_R

Incentive Program (Summary Of Restricted Stock And Units Outstanding) (Details) (USD $)	12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2014
Incentive Program [Abstract]
Issued and outstanding at January 1, Restricted stock, Shares	45,207
2013 award issued in 2014, Shares	9,705
Vested, Shares	-10,286
Forfeited, Shares	-187
Issued and outstanding at December 31, Restricted stock, Shares	44,439
Issued and outstanding at January 1, Weighted Average Grant-Date Fair Value per Share	$78.29
2013 award issued in 2014, Weighted Average Grant-Date Fair Value per Share	$94.47
Vested, Weighted Average Grant-Date Fair Value per Share	$79.89
Forfeited, Weighted Average Grant-Date Fair Value per Share	$78.89
Issued and outstanding at December 31, Weighted Average Grant-Date Fair Value per Share	$81.45

Incentive_Program_Grant_Value_

Incentive Program (Grant Value Of Restricted Stock And Units) (Details) (USD $)	12 Months Ended
In Millions, except Per Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Grant price, per share	$95.20	$94.47	$87.24
Restricted stock and units settled in stock	$858	$843	$797
Units settled in cash	73	76	77
Total value	$931	$919	$874

Litigation_And_Other_Contingen2

Litigation And Other Contingencies (Narrative) (Details) (USD $)	3 Months Ended
	Dec. 31, 2014	Oct. 09, 2014	Jun. 27, 2007	1-May-07	Oct. 24, 2011
Mobil Cerro Negro, Ltd. (MCN) [Member] | Expropriation of Assets [Member]
Loss Contingencies [Line Items]
Percentage ownership interest in Cerro Negro Project			41.67%	41.67%
Interest compounded annually from date of expropriation until date of payment in full		3.25%
Final award related to Cerro Negro arbitration		$1,600,000,000
Earlier Cerro Negro award for breach of contractual obligations		908,000,000
Recognized earnings net of the remaining asset value from earlier ICC award	269,000,000
Production Sharing Contract (PSC) [Member]
Loss Contingencies [Line Items]
Percent interest in Erha block PSC					56.25%
Pending Or Threatened Litigation [Member]
Loss Contingencies [Line Items]
Amount of award relating to excess lifting of crude oil					1,800,000,000
Accrued interest relating to award for excess lifting of crude oil					234,000,000

Litigation_And_Other_Contingen3

Litigation And Other Contingencies (Schedule Of Guarantees) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Loss Contingencies [Line Items]
Guarantees	$10,449
Equity Company Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	6,426	[1]
Other Third-Party Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	4,023
Debt-Related Guarantees [Member]
Loss Contingencies [Line Items]
Guarantees	3,547
Debt-Related Guarantees [Member] | Papua New Guinea Liquefied Natural Gas Project [Member]
Loss Contingencies [Line Items]
Guarantees	3,400
Debt-Related Guarantees [Member] | Equity Company Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	3,506	[1]
Debt-Related Guarantees [Member] | Other Third-Party Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	41
Other Guarantees [Member]
Loss Contingencies [Line Items]
Guarantees	6,902
Other Guarantees [Member] | Equity Company Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	2,920	[1]
Other Guarantees [Member] | Other Third-Party Obligations [Member]
Loss Contingencies [Line Items]
Guarantees	$3,982
[1]	ExxonMobil share

Litigation_And_Other_Contingen4

Litigation And Other Contingencies (Schedule Of Unconditional Purchase Obligations) (Details) (USD $)	Dec. 31, 2014
In Millions, unless otherwise specified
Unrecorded Unconditional Purchase Obligation [Line Items]
2015	$150
2016-2019	608
2020 and Beyond	337
Total	1,095	[1]
Present value of these commitments	927
Undiscounted unconditional purchase obligations	1,095	[1]
Imputed interest	168
Equity Company Obligations [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Total	433
Undiscounted unconditional purchase obligations	$433
[1]	Undiscounted obligations of $1,095 million mainly pertain to pipeline throughput agreements and include $433 million of obligations to equity companies. The present value of these commitments, which excludes imputed interest of $168 million, totaled $927 million.

Pension_And_Other_Postretireme2

Pension And Other Postretirement Benefits (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate projected in 2016	4.50%
Year that rate reaches ultimate trend rate	2016
Effect of one-percentage-point increase on service and interest costs	$91
Effect of one-percentage-point increase on postretirement benefit obligation	1,070
Effect of one-percentage-point decrease on service and interest costs	69
Effect of one-percentage-point decrease on postretirement benefit obligation	844
Costs for defined contribution plans	$393	$392	$382
Pension Benefits - U.S. [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	40.00%
Pension Benefits - U.S. [Member] | Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	60.00%
Pension Benefits - U.S. [Member] | Venture Capital Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	5.00%
Pension Benefits - Non-U.S. [Member] | Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	40.00%
Pension Benefits - Non-U.S. [Member] | Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	60.00%
Pension Benefits - Non-U.S. [Member] | Venture Capital Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocation	3.00%

Pension_And_Other_Postretireme3

Pension And Other Postretirement Benefits (Benefit Obligations And Plan Assets Associated With Principal Benefit Plans) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Medicare subsidy receipts	$21		$20
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%		5.00%
Long-term rate of compensation increase	5.75%		5.75%
Benefit obligation at January 1	17,304		19,779
Service cost	677		801		665
Interest cost	807		749		820
Defined Benefit Plan, Actuarial Net (Gains) Losses	3,192		-1,520
Amendments, divestments and other	-24		15
Benefit obligation at December 31	20,529		17,304		19,779
Accumulated benefit obligation at December 31	16,385		13,989
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.10%		4.30%
Long-term rate of compensation increase	5.30%		5.40%
Benefit obligation at January 1	27,357		28,670
Service cost	590		697		648
Interest cost	1,138		1,076		1,145
Defined Benefit Plan, Actuarial Net (Gains) Losses	4,929		-1,454
Foreign exchange rate changes	-2,540		-284
Amendments, divestments and other	-61		-37
Benefit obligation at December 31	30,047		27,357		28,670
Accumulated benefit obligation at December 31	26,318		23,949
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%		5.00%
Long-term rate of compensation increase	5.75%		5.75%
Benefit obligation at January 1	7,868		9,058
Service cost	140		176		134
Interest cost	383		352		380
Defined Benefit Plan, Actuarial Net (Gains) Losses	1,522		-1,267
Foreign exchange rate changes	-48		-43
Amendments, divestments and other	96		103
Benefit obligation at December 31	9,436		7,868		9,058
Benefit Payments For Funded And Unfunded Plans [Member] | Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	-1,427	[1]	-2,520	[1]
Benefit Payments For Funded And Unfunded Plans [Member] | Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	-1,366	[1]	-1,311	[1]
Benefit Payments For Funded And Unfunded Plans [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	($525)	[1],[2]	($511)	[1],[2]
[1]	Benefit payments for funded and unfunded plans.
[2]	For 2014 and 2013, other postretirement benefits paid are net of $21 million and $20 million of Medicare subsidy receipts, respectively.

Pension_And_Other_Postretireme4

Pension And Other Postretirement Benefits (Change In Plan Assets Of Pension And Other Postretirement Benefits) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	$11,190		$12,632
Actual return on plan assets	1,497		617
Company contribution	1,476		101
Other			11
Fair value at December 31	12,915		11,190
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	19,283		18,090
Actual return on plan assets	3,153		1,604
Foreign exchange rate changes	-1,738		-270
Company contribution	554		919
Other	-245		-191
Fair value at December 31	20,095		19,283
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	620		581
Actual return on plan assets	41		64
Company contribution	31		35
Fair value at December 31	468		620
Benefit Payments For Funded Plans [Member] | Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	-1,248	[1]	-2,171	[1]
Benefit Payments For Funded Plans [Member] | Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	-912	[1]	-869	[1]
Benefit Payments For Funded Plans [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits paid	($224)	[1]	($60)	[1]
[1]	Benefit payments for funded plans.

Pension_And_Other_Postretireme5

Pension And Other Postretirement Benefits (Summary Of Assets In Excess Of/(Less Than) Benefit Obligation) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Funded Status of Plan	($4,590)		($3,547)
Unfunded plans	-3,024		-2,567
Total	-7,614	[1]	-6,114	[1]
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Funded Status of Plan	-2,113		-941
Unfunded plans	-7,839		-7,133
Total	($9,952)	[1]	($8,074)	[1]
[1]	Fair value of assets less benefit obligation shown on the preceding page.

Pension_And_Other_Postretireme6

Pension And Other Postretirement Benefits (Assets Recorded In Balance Sheet And Other Comprehensive Income) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Millions, unless otherwise specified
Defined Benefit Plan Disclosure [Line Items]
Postretirement benefits reserves	($25,802)		($20,646)
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Balance at December 31	-7,614	[1]	-6,114	[1]
Other assets			1
Current liabilities	-340		-275
Postretirement benefits reserves	-7,274		-5,840
Total recorded	-7,614		-6,114
Net actuarial loss/(gain)	6,589		4,780
Prior service cost	27		60
Total recorded in accumulated other comprehensive income	6,616		4,840
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Balance at December 31	-9,952	[1]	-8,074	[1]
Other assets	302		201
Current liabilities	-325		-358
Postretirement benefits reserves	-9,929		-7,917
Total recorded	-9,952		-8,074
Net actuarial loss/(gain)	9,642		7,943
Prior service cost	429		665
Total recorded in accumulated other comprehensive income	10,071		8,608
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Balance at December 31	-8,968	[1]	-7,248	[1]
Current liabilities	-369		-359
Postretirement benefits reserves	-8,599		-6,889
Total recorded	-8,968		-7,248
Net actuarial loss/(gain)	2,997		1,603
Prior service cost	51		65
Total recorded in accumulated other comprehensive income	$3,048		$1,668
[1]	Fair value of assets less benefit obligation shown on the preceding page.

Pension_And_Other_Postretireme7

Pension And Other Postretirement Benefits (Long-Term Rates Of Pension And Other Postretirement Benefits) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Total recorded in other comprehensive income	$4,619	($7,281)	$1,523
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.00%	4.00%	5.00%
Long-term rate of return on funded assets	7.25%	7.25%	7.25%
Long-term rate of compensation increase	5.75%	5.75%	5.75%
Service cost	677	801	665
Interest cost	807	749	820
Expected return on plan assets	-799	-835	-789
Amortization of actuarial loss/(gain)	409	646	576
Amortization of prior service cost	8	7	7
Net pension enhancement and curtailment/settlement cost	276	723	333
Net periodic benefit cost	1,378	2,091	1,612
Net actuarial loss/(gain)	2,494	-1,302	1,885
Amortization of actuarial (loss)/gain	-685	-1,369	-909
Prior service cost/(credit)	-25
Amortization of prior service (cost)/credit	-8	-7	-7
Total recorded in other comprehensive income	1,776	-2,678	969
Total recorded in net periodic benefit cost and other comprehensive income, before tax	3,154	-587	2,581
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.30%	3.80%	4.00%
Long-term rate of return on funded assets	6.30%	6.40%	6.60%
Long-term rate of compensation increase	5.40%	5.50%	5.40%
Service cost	590	697	648
Interest cost	1,138	1,076	1,145
Expected return on plan assets	-1,193	-1,128	-1,109
Amortization of actuarial loss/(gain)	628	852	844
Amortization of prior service cost	120	117	117
Net pension enhancement and curtailment/settlement cost		22	1,540	[1]
Net periodic benefit cost	1,283	1,636	3,185
Net actuarial loss/(gain)	2,969	-1,938	1,906
Amortization of actuarial (loss)/gain	-628	-874	-2,384
Prior service cost/(credit)	-70	30	71
Amortization of prior service (cost)/credit	-120	-117	-117
Foreign exchange rate changes	-688	-155	271
Total recorded in other comprehensive income	1,463	-3,054	-253
Total recorded in net periodic benefit cost and other comprehensive income, before tax	2,746	-1,418	2,932
Pension Benefits - Non-U.S. [Member] | Japan Transaction Disposal Group [Member]
Defined Benefit Plan Disclosure [Line Items]
Net pension enhancement and curtailment/settlement cost		1,420
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	5.00%	4.00%	5.00%
Long-term rate of return on funded assets	7.25%	7.25%	7.25%
Long-term rate of compensation increase	5.75%	5.75%	5.75%
Service cost	140	176	134
Interest cost	383	352	380
Expected return on plan assets	-37	-41	-38
Amortization of actuarial loss/(gain)	116	228	170
Amortization of prior service cost	14	21	34
Net periodic benefit cost	616	736	680
Net actuarial loss/(gain)	1,518	-1,290	1,008
Amortization of actuarial (loss)/gain	-116	-228	-170
Amortization of prior service (cost)/credit	-14	-21	-34
Foreign exchange rate changes	-8	-10	3
Total recorded in other comprehensive income	1,380	-1,549	807
Total recorded in net periodic benefit cost and other comprehensive income, before tax	$1,996	($813)	$1,487
[1]	Non-U.S. net pension enhancement and curtailment/settlement cost for 2012 includes $1,420 million (on a consolidated-company, before-tax basis) of accumulated other comprehensive income for the postretirement benefit reserves adjustment that was recycled into earnings and included in the Japan restructuring gain reported in bOther incomeb.

Pension_And_Other_Postretireme8

Pension And Other Postretirement Benefits (Summary Of The Change In Accumulated Other Comprehensive Income) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Total (charge)/credit to other comprehensive income, before tax	($4,619)	$7,281	($1,523)
(Charge)/credit to income tax (see Note 4)	1,549	-2,336	393
(Charge)/credit to investment in equity companies	-81	49	-49
(Charge)/credit to other comprehensive income including noncontrolling interests, after tax	-3,151	4,994	-1,179
Charge/(credit) to equity of noncontrolling interests	85	-279	-124
(Charge)/credit to other comprehensive income attributable to ExxonMobil	-3,066	4,715	-1,303
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Total (charge)/credit to other comprehensive income, before tax	-1,776	2,678	-969
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Total (charge)/credit to other comprehensive income, before tax	-1,463	3,054	253
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Total (charge)/credit to other comprehensive income, before tax	($1,380)	$1,549	($807)

Pension_And_Other_Postretireme9

Pension And Other Postretirement Benefits (Fair Value Of Benefit Plan Assets) (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
In Millions, unless otherwise specified
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Insurance contracts at contract value	$11		$12
Fair value of plan assets	12,915		11,190		12,632
Pension Benefits - U.S. [Member] | U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,331		2,514
Pension Benefits - U.S. [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,144		2,622
Pension Benefits - U.S. [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	562		523
Pension Benefits - U.S. [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,841		3,430
Pension Benefits - U.S. [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,890		2,056
Pension Benefits - U.S. [Member] | Asset-Backed Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5		6
Pension Benefits - U.S. [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	131		27
Pension Benefits - U.S. [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,904		11,178
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,331	[1]	2,514	[1]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,144	[1]	2,622	[1]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,841	[2]	3,430	[2]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,890	[2]	2,056	[2]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Asset-Backed Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5	[2]	6	[2]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	131	[3]	27	[3]
Pension Benefits - U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	12,342		10,655
Pension Benefits - U.S. [Member] | Significant Unobservable Inputs (Level 3) [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	562	[4]	523	[4]
Pension Benefits - U.S. [Member] | Significant Unobservable Inputs (Level 3) [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	562		523
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Insurance contracts at contract value	27		20
Fair value of plan assets	20,095		19,283		18,090
Pension Benefits - Non-U.S. [Member] | U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,284		3,046
Pension Benefits - Non-U.S. [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,005		5,902
Pension Benefits - Non-U.S. [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	535		502
Pension Benefits - Non-U.S. [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,686		2,125
Pension Benefits - Non-U.S. [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,299		7,372
Pension Benefits - Non-U.S. [Member] | Asset-Backed Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	146		103
Pension Benefits - Non-U.S. [Member] | Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	57		136
Pension Benefits - Non-U.S. [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	56		77
Pension Benefits - Non-U.S. [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	20,068		19,263
Pension Benefits - Non-U.S. [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	229	[5]	294	[5]
Pension Benefits - Non-U.S. [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	249	[6]	272	[6]
Pension Benefits - Non-U.S. [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	25		57
Pension Benefits - Non-U.S. [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	503		623
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,284	[1]	3,046	[1]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3,776	[1]	5,608	[1]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,686	[2]	2,125	[2]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9,050	[2]	7,100	[2]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Asset-Backed Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	146	[2]	103	[2]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	31	[7]	20	[7]
Pension Benefits - Non-U.S. [Member] | Significant Other Observable Inputs (Level 2) [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	18,973		18,002
Pension Benefits - Non-U.S. [Member] | Significant Unobservable Inputs (Level 3) [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	535	[4]	502	[4]
Pension Benefits - Non-U.S. [Member] | Significant Unobservable Inputs (Level 3) [Member] | Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	57	[8]	136	[8]
Pension Benefits - Non-U.S. [Member] | Significant Unobservable Inputs (Level 3) [Member] | Total At Fair Value [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$592		$638
[1]	For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
[2]	For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
[3]	For cash balances held in the form of short-term fund units that are redeemable at the measurement date, the fair value is treated as a Level 2 input.
[4]	For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.
[5]	For non-U.S. equity securities held in separate accounts, fair value is based on observable quoted prices on active exchanges.
[6]	For corporate and government debt securities that are traded on active exchanges, fair value is based on observable quoted prices.
[7]	For cash balances that are subject to withdrawal penalties or other adjustments, the fair value is treated as a Level 2 input.
[8]	For real estate funds, fair value is based on appraised values developed using comparable market transactions.

Recovered_Sheet1

Pension And Other Postretirement Benefits (Fair Value Of Benefit Plan Assets - Other Postretirement) (Details) (Other Postretirement Benefit Plans Defined Benefit [Member], USD $)	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
In Millions, unless otherwise specified
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$468		$620		$581
U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106		157
Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75		149
Private Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2		9
Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	103		129
Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	171		168
Asset Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9		4
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2		4
Fair Value Inputs Level2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	466		611
Fair Value Inputs Level2 [Member] | U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	106	[1]	157	[1]
Fair Value Inputs Level2 [Member] | Non-U.S. Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75	[1]	149	[1]
Fair Value Inputs Level2 [Member] | Corporate Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	103	[2]	129	[2]
Fair Value Inputs Level2 [Member] | Government Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	171	[2]	168	[2]
Fair Value Inputs Level2 [Member] | Asset Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	9	[2]	4	[2]
Fair Value Inputs Level2 [Member] | Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2		4
Fair Value Inputs Level3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2		9
Fair Value Inputs Level3 [Member] | Private Equity Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$2	[3]	$9	[3]
[1]	For U.S. and non-U.S. equity securities held in the form of fund units that are redeemable at the measurement date, the unit value is treated as a Level 2 input. The fair value of the securities owned by the funds is based on observable quoted prices on active exchanges, which are Level 1 inputs.
[2]	For corporate, government and asset-backed debt securities, fair value is based on observable inputs of comparable market transactions.
[3]	For private equity, fair value is generally established by using revenue or earnings multiples or other relevant market data including Initial Public Offerings.

Recovered_Sheet2

Pension And Other Postretirement Benefits (Change In The Fair Value Of Level 3 Assets) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits - U.S. [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	$523	$489
Net realized gains/(losses)	2	-1
Net unrealized gains/(losses)	89	86
Net purchases/(sales)	-52	-51
Fair value at December 31	562	523
Pension Benefits - Non-U.S. [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	502	448
Net realized gains/(losses)	23	11
Net unrealized gains/(losses)	31	57
Net purchases/(sales)	-21	-14
Fair value at December 31	535	502
Pension Benefits - Non-U.S. [Member] | Real Estate Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	136	293
Net realized gains/(losses)	-17	-13
Net unrealized gains/(losses)	8	10
Net purchases/(sales)	-70	-154
Fair value at December 31	57	136
Other Postretirement Benefits [Member] | Private Equity [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value at January 1	9	7
Net unrealized gains/(losses)		3
Net purchases/(sales)	-7	-1
Fair value at December 31	$2	$9

Recovered_Sheet3

Pension And Other Postretirement Benefits (Pension Plans With Accumulated Benefit Obligation In Excess Of Plan Assets) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Funded Pension Plans [Member] | Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$17,505	$14,737
Accumulated benefit obligation	14,493	12,342
Fair value of plan assets	12,915	11,189
Funded Pension Plans [Member] | Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	5,031	891
Accumulated benefit obligation	4,590	689
Fair value of plan assets	3,890	611
Unfunded Pension Plans [Member] | Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	3,024	2,567
Accumulated benefit obligation	1,892	1,647
Unfunded Pension Plans [Member] | Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	7,839	7,133
Accumulated benefit obligation	$6,573	$6,070

Recovered_Sheet4

Pension And Other Postretirement Benefits (Estimated Amortization) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss/(gain)	$1,001	[1]
Prior service cost	6	[2]
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss/(gain)	753	[1]
Prior service cost	105	[2]
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss/(gain)	211	[1]
Prior service cost	$14	[2]
[1]	The Corporation amortizes the net balance of actuarial losses/(gains) as a component of net periodic benefit cost over the average remaining service period of active plan participants.
[2]	The Corporation amortizes prior service cost on a straight-line basis as permitted under authoritative guidance for defined benefit pension and other postretirement benefit plans.

Recovered_Sheet5

Pension And Other Postretirement Benefits (Expected Contribution Pension Benefits And Other Postretirement Benefits) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014
Pension Benefits - U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits payments expected in 2015	$1,628
Benefits payments expected in 2016	1,554
Benefits payments expected in 2017	1,529
Benefits payments expected in 2018	1,445
Benefits payments expected in 2019	1,410
Benefits payments expected in 2020-2024	6,714
Pension Benefits - Non-U.S. [Member]
Defined Benefit Plan Disclosure [Line Items]
Contributions expected in 2015	560
Benefits payments expected in 2015	1,194
Benefits payments expected in 2016	1,213
Benefits payments expected in 2017	1,278
Benefits payments expected in 2018	1,298
Benefits payments expected in 2019	1,339
Benefits payments expected in 2020-2024	6,988
Gross Other Post Retirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits payments expected in 2015	467
Benefits payments expected in 2016	479
Benefits payments expected in 2017	490
Benefits payments expected in 2018	499
Benefits payments expected in 2019	507
Benefits payments expected in 2020-2024	2,613
Other Postretirement Benefits Medicare Subsidy Receipt [Member]
Defined Benefit Plan Disclosure [Line Items]
Benefits payments expected in 2015	24
Benefits payments expected in 2016	25
Benefits payments expected in 2017	26
Benefits payments expected in 2018	28
Benefits payments expected in 2019	29
Benefit payments expected in 2020-2024	$172

Disclosures_About_Segments_And2

Disclosures About Segments And Related Information (Narrative) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Disclosures About Segments And Related Information [Abstract]
Non-debt-related interest expense	$129	($123)	$202

Disclosures_About_Segments_And3

Disclosures About Segments And Related Information (Schedule Of Segments And Related Information) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Earnings after income tax	$32,520		$32,580		$44,880
Earnings of equity companies included above	13,323		13,927		15,010
Sales and other operating revenue	394,105	[1],[2]	420,836	[1],[2]	451,509	[1],[2]
Depreciation and depletion expense	17,297		17,182		15,888
Interest revenue	75		87		117
Interest expense	286		9		327
Income taxes	18,015		24,263		31,045
Additions to property, plant and equipment	34,256		37,741		35,179
Investments in equity companies	20,017		19,619		18,530
Total assets	349,493		346,808		333,795
U.S. [Member]
Income taxes	1,862		1,391		3,579
Non-U.S. [Member]
Income taxes	16,153		22,872		27,466
Upstream [Member] | U.S. [Member]
Earnings after income tax	5,197		4,191		3,925
Earnings of equity companies included above	1,235		1,576		1,759
Sales and other operating revenue	14,826	[2]	13,712	[2]	11,039	[2]
Intersegment revenue	7,723		8,343		8,764
Depreciation and depletion expense	5,139		5,170		5,104
Interest expense	40		30		37
Income taxes	1,300		2,197		2,025
Additions to property, plant and equipment	9,098		7,480		9,697
Investments in equity companies	5,089		4,975		4,020
Total assets	92,555		88,698		86,146
Upstream [Member] | Non-U.S. [Member]
Earnings after income tax	22,351		22,650		25,970
Earnings of equity companies included above	10,859		11,627		11,900
Sales and other operating revenue	22,336	[2]	25,349	[2]	27,673	[2]
Intersegment revenue	38,846		45,761		47,507
Depreciation and depletion expense	8,523		8,277		7,340
Interest expense	17		26		13
Income taxes	15,165		21,554		25,362
Additions to property, plant and equipment	19,225		26,075		21,769
Investments in equity companies	10,877		9,740		9,147
Total assets	161,033		157,465		140,848
Downstream [Member] | U.S. [Member]
Earnings after income tax	1,618		2,199		3,575
Earnings of equity companies included above	29		-460		6
Sales and other operating revenue	118,771	[2]	123,802	[2]	125,088	[2]
Intersegment revenue	17,281		20,781		20,963
Depreciation and depletion expense	654		633		594
Interest expense	6		7		3
Income taxes	610		721		1,811
Additions to property, plant and equipment	1,050		616		480
Investments in equity companies	69		62		195
Total assets	18,371		19,261		18,451
Downstream [Member] | Non-U.S. [Member]
Earnings after income tax	1,427		1,250		9,615
Earnings of equity companies included above	82		22		387
Sales and other operating revenue	199,976	[2]	218,904	[2]	248,959	[2]
Intersegment revenue	44,231		52,624		62,130
Depreciation and depletion expense	1,228		1,390		1,280
Interest expense	4		8		36
Income taxes	968		481		1,892
Additions to property, plant and equipment	1,356		1,072		1,153
Investments in equity companies	1,006		1,749		2,069
Total assets	33,299		40,661		40,956
Chemical [Member] | U.S. [Member]
Earnings after income tax	2,804		2,755		2,220
Earnings of equity companies included above	186		189		183
Sales and other operating revenue	15,115	[2]	15,295	[2]	14,723	[2]
Intersegment revenue	10,117		11,993		12,409
Depreciation and depletion expense	370		378		376
Interest expense			1
Income taxes	1,032		989		755
Additions to property, plant and equipment	1,564		840		338
Investments in equity companies	258		217		233
Total assets	8,798		7,816		7,238
Chemical [Member] | Non-U.S. [Member]
Earnings after income tax	1,511		1,073		1,678
Earnings of equity companies included above	1,377		1,422		1,267
Sales and other operating revenue	23,063	[2]	23,753	[2]	24,003	[2]
Intersegment revenue	8,098		8,232		9,750
Depreciation and depletion expense	645		632		508
Interest expense					-1
Income taxes	358		363		232
Additions to property, plant and equipment	564		272		659
Investments in equity companies	3,026		3,103		3,143
Total assets	18,449		19,659		18,886
Corporate And Financing [Member]
Earnings after income tax	-2,388		-1,538		-2,103
Earnings of equity companies included above	-445		-449		-492
Sales and other operating revenue	18	[2]	21	[2]	24	[2]
Intersegment revenue	274		285		258
Depreciation and depletion expense	738		702		686
Interest revenue	75		87		117
Interest expense	219		-63		239
Income taxes	-1,418		-2,042		-1,032
Additions to property, plant and equipment	1,399		1,386		1,083
Investments in equity companies	-308		-227		-277
Total assets	$16,988		$13,248		$21,270
[1]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012.
[2]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.

Disclosures_About_Segments_And4

Disclosures About Segments And Related Information (Schedule Of Geographic Sales And Other Operating Revenue) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	$394,105	[1]	$420,836	[1]	$451,509	[1]
Sales-based taxes	29,342	[2]	30,589	[2]	32,409	[2]
U.S. [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	148,713	[1]	152,820	[1]	150,865	[1]
Sales-based taxes	6,310		5,992		5,785
Non-U.S. [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	245,392	[1]	268,016	[1]	300,644	[1]
Sales-based taxes	23,032		24,597		26,624
Canada [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	36,072	[1]	35,924	[1]	34,325	[1]
United Kingdom [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	31,346	[1]	34,061	[1]	33,600	[1]
Belgium [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	20,953	[1]	20,973	[1]	23,567	[1]
Italy [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	18,880	[1]	19,273	[1]	18,228	[1]
France [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	17,639	[1]	18,444	[1]	19,601	[1]
Singapore [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	15,407	[1]	15,623	[1]	14,606	[1]
Germany [Member]
Segment Reporting Revenue Reconciling Item [Line Items]
Sales and other operating revenue	$14,816	[1]	$15,701	[1]	$15,871	[1]
[1]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012. See Note 1, Summary of Accounting Policies.
[2]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012.

Disclosures_About_Segments_And5

Disclosures About Segments And Related Information (Schedule Of Long-Lived Assets By Geographic Regions) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Long-lived assets	$252,668	$243,650	$226,949
U.S. [Member]
Long-lived assets	104,000	98,271	94,336
Non-U.S. [Member]
Long-lived assets	148,668	145,379	132,613
Canada [Member]
Long-lived assets	43,858	41,522	31,979
Australia [Member]
Long-lived assets	15,328	14,258	13,415
Nigeria [Member]
Long-lived assets	12,265	12,343	12,216
Singapore [Member]
Long-lived assets	9,620	9,570	9,700
Kazakhstan [Member]
Long-lived assets	9,138	8,530	7,785
Angola [Member]
Long-lived assets	9,057	8,262	8,238
Papua New Guinea [Member]
Long-lived assets	6,099	5,768	4,599
Norway [Member]
Long-lived assets	$5,139	$6,542	$7,040

Income_SalesBased_And_Other_Ta2

Income, Sales-Based And Other Taxes (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income, Sales-Based And Other Taxes [Abstract]
Net deferred income tax expense (credits)/charges for tax rate and law changes	($40,000,000)	($310,000,000)	$244,000,000
Reconciliation between income tax expense and theoretical U.S. tax rate, statutory rate	35.00%	35.00%	35.00%
Indefinitely reinvested, undistributed earnings from subsidiary companies outside the U.S.	51,000,000,000
Potential percentage increase in unrecognized tax benefits	30.00%
Credit of net interest expense on income tax reserves		207,000,000
Interest expense on income tax reserves	42,000,000		46,000,000
Interest payable on income tax reserves	205,000,000	156,000,000
Statement [Line Items]
Asset valuation allowances	2,570,000,000	2,491,000,000
Valuation Allowance increase from 2013 to 2014	79,000,000
Additional net provisions [Member]
Statement [Line Items]
Valuation Allowance increase from 2013 to 2014	340,000,000
Effects of foreign currency translation [Member]
Statement [Line Items]
Valuation Allowance increase from 2013 to 2014	($261,000,000)

Income_SalesBased_And_Other_Ta3

Income, Sales-Based And Other Taxes (Schedule Of Income, Sales-Based And Other Taxes) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Income, Sales-Based and Other Taxes [Line Items]
Current	$16,211		$23,188		$27,441
Deferred - net	2,298		641		2,913
U.S. tax on non-U.S. operations	5		37		89
Total federal and non-U.S.	18,514		23,866		30,443
State	-499	[1]	397		602
Total income tax expense	18,015		24,263		31,045
Sales-based taxes	29,342	[2]	30,589	[2]	32,409	[2]
Other taxes and duties	32,286		33,230		35,558
Other taxes and duties included in production and manufacturing expenses	2,633		2,500		2,550
Other taxes and duties included in SG&A expenses	596		666		749
Total other taxes and duties	35,515		36,396		38,857
Total	82,872		91,248		102,311
U.S. [Member]
Income, Sales-Based and Other Taxes [Line Items]
Current	1,456		1,073		1,791
Deferred - net	900		-116		1,097
U.S. tax on non-U.S. operations	5		37		89
Total federal and non-U.S.	2,361		994		2,977
State	-499	[1]	397		602
Total income tax expense	1,862		1,391		3,579
Sales-based taxes	6,310		5,992		5,785
Other taxes and duties	378		955		1,406
Other taxes and duties included in production and manufacturing expenses	1,454		1,318		1,242
Other taxes and duties included in SG&A expenses	155		150		154
Total other taxes and duties	1,987		2,423		2,802
Total	10,159		9,806		12,166
U.S. [Member] | State Tax Adjustment [Member]
Income, Sales-Based and Other Taxes [Line Items]
Deferred tax adjustment included in State Taxes	830
Non-U.S. [Member]
Income, Sales-Based and Other Taxes [Line Items]
Current	14,755		22,115		25,650
Deferred - net	1,398		757		1,816
Total federal and non-U.S.	16,153		22,872		27,466
Total income tax expense	16,153		22,872		27,466
Sales-based taxes	23,032		24,597		26,624
Other taxes and duties	31,908		32,275		34,152
Other taxes and duties included in production and manufacturing expenses	1,179		1,182		1,308
Other taxes and duties included in SG&A expenses	441		516		595
Total other taxes and duties	33,528		33,973		36,055
Total	$72,713		$81,442		$90,145
[1]	In 2014, state taxes included a favorable adjustment of deferred taxes of approximately $830 million.
[2]	Sales and other operating revenue includes sales-based taxes of $29,342 million for 2014, $30,589 million for 2013 and $32,409 million for 2012.

Income_SalesBased_And_Other_Ta4

Income, Sales-Based And Other Taxes (Reconciliation Between Income Tax Expense And Theoretical U.S. Tax) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income, Sales-Based And Other Taxes [Abstract]
United States Income before income taxes	$9,080	$9,746	$11,222
Non-U.S. Income before income taxes	42,550	47,965	67,504
Income before income taxes	51,630	57,711	78,726
Theoretical tax	18,071	20,199	27,554
Effect of equity method of accounting	-4,663	-4,874	-5,254
Non-U.S. taxes in excess of theoretical U.S. tax	5,442	10,528	8,434
U.S. tax on non-U.S. operations	5	37	89
State taxes, net of federal tax benefit	-324	258	391
Other	-516	-1,885	-169
Total income tax expense	18,015	24,263	31,045
ExxonMobil share of equity company income taxes	5,678	6,061	5,859
Total income taxes	23,693	30,324	36,904
Net income including noncontrolling interests	33,615	33,448	47,681
Total income before taxes	$57,308	$63,772	$84,585
Effective income tax rate	41.00%	48.00%	44.00%

Income_SalesBased_And_Other_Ta5

Income, Sales-Based And Other Taxes (Deferred Income Taxes Assets And Liabilities) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Income, Sales-Based And Other Taxes [Abstract]
Property, plant and equipment	$51,643	$50,884
Other liabilities	4,359	3,474
Total deferred tax liabilities	56,002	54,358
Pension and other postretirement benefits	-8,140	-6,573
Asset retirement obligations	-6,162	-6,083
Tax loss carryforwards	-4,099	-3,393
Other assets	-6,446	-6,246
Total deferred tax assets	-24,847	-22,295
Asset valuation allowances	2,570	2,491
Net deferred tax liabilities	$33,725	$34,554

Income_SalesBased_And_Other_Ta6

Income, Sales-Based And Other Taxes (Deferred Income Tax (Assets) And Liabilities By Balance Sheet Classification) (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Income, Sales-Based And Other Taxes [Abstract]
Other current assets	($2,001)	($3,575)
Other assets, including intangibles, net	-3,955	-2,822
Accounts payable and accrued liabilities	451	421
Deferred income tax liabilities	39,230	40,530
Net deferred tax liabilities	$33,725	$34,554

Income_SalesBased_And_Other_Ta7

Income, Sales-Based And Other Taxes (Unrecognized Tax Benefits) (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income, Sales-Based And Other Taxes [Abstract]
Balance at January 1	$7,838	$7,663	$4,922
Additions based on current year's tax positions	1,454	1,460	1,662
Additions for prior years' tax positions	448	464	2,559
Reductions for prior years' tax positions	-532	-249	-535
Reductions due to lapse of the statute of limitations	-117	-588	-79
Settlements with tax authorities	-43	-849	-855
Foreign exchange effects / other	-62	-63	-11
Balance at December 31	$8,986	$7,838	$7,663

Income_SalesBased_And_Other_Ta8

Income, Sales-Based And Other Taxes (Remaining Tax Years Subject To Examination By Major Tax Jurisdiction) (Details)	12 Months Ended
	Dec. 31, 2014
Abu Dhabi [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Abu Dhabi [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2012
Angola [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Angola [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2009
Australia [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2003
Australia [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2000
Australia Second Range [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2005
Australia Second Range [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2005
Australia Third Range [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Australia Third Range [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2008
Canada [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Canada [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2007
Equatorial Guinea [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Equatorial Guinea [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2007
Malaysia [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Malaysia [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2008
Nigeria [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Nigeria [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2004
Norway [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Norway [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2005
Qatar [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Qatar [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2008
Russia [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
Russia [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2011
United Kingdom [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
United Kingdom [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2010
United States [Member] | Maximum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2014
United States [Member] | Minimum [Member]
Income, Sales-Based and Other Taxes [Line Items]
Open Tax Years by major tax jurisdiction	2006