Miscellaneous Financial Information (Crude Oil, Products And Merchandise) (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Crude oil	$ 6,483	$ 6,944
Petroleum products	6,017	6,248
Chemical products	4,142	3,930
Gas/other	2,802	3,406
Total	$ 19,444	$ 20,528

Carrying amount as of the balance sheet date of merchandise, goods, commodities, or supplies relating to a source of usable power held for future sale or future use in manufacturing or production process.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(6)(a))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of solvents or substances produced by or used in a process to change the shape, form or composition of some related matter.

+ References

+ Details

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- Definition

Carrying amount as of the balance sheet date of petroleum or crude oil.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of finished goods inventories for petroleum products, crude oil, petrochemical products, and other oil and gas inventories.

+ References

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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- References

No definition available.

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- Definition

Environmental Certificates and Natural Gas

+ References

No definition available.

+ Details

Name:	xom_NaturalGasAndOtherInventory
Namespace Prefix:	xom_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant