The value (monetary amount) of the additional award the plaintiff seeks in the legal matter.

No definition available.

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Namespace Prefix:	ibm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The value (monetary amount) of the direct damages awarded to the plaintiff which were subsequently appealed in the course of a legal matter.

+ References

No definition available.

+ Details

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Namespace Prefix:	ibm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The value (monetary amount) of the punitive damages awarded to the plaintiff which were subsequently appealed in the course of a legal matter.

+ References

No definition available.

+ Details

Name:	ibm_LossContingencyPunitiveDamagesAwardedAndAppealed
Namespace Prefix:	ibm_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of former executives of the reporting entity named as defendants.

+ References

No definition available.

+ Details

Name:	ibm_NumberOfFormerExecutivesNamedAsDefendants
Namespace Prefix:	ibm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

the number of officers or executives of the reporting entity named as defendants.

+ References

No definition available.

+ Details

Name:	ibm_NumberOfOfficerOrExecutivesNamedAsDefendants
Namespace Prefix:	ibm_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LossContingenciesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121557415&loc=d3e14557-108349

+ Details

Name:	us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

+ Details

Name:	us-gaap_LossContingencyNewClaimsFiledNumber
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of countries in which the entity operates as of balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfCountriesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_LitigationCaseAxis=ibm_BmcV.IbmMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=ibm_LitigationCaseInUnitedStatesDistrictCourtRegardingPutativeSecuritiesClassActionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LossContingenciesByNatureOfContingencyAxis=ibm_BrazilTaxMattersMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_LitigationCaseAxis=ibm_IbmVsGlobalFoundriesU.s.IncMember
Namespace Prefix:
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Commitments & Contingencies - Contingencies (Details) $ in Millions				1 Months Ended		12 Months Ended
	May 30, 2022 USD ($)	Apr. 05, 2022 defendant	Jun. 08, 2021 USD ($)	Apr. 30, 2022 USD ($)	Feb. 28, 2021 USD ($)	Dec. 31, 2022 USD ($) claim country
CISGIL v. IBM UK
Loss Contingencies
Amount of award against IBM					$ 20
Additional damages sought, value				$ 89
BMC v. IBM
Loss Contingencies
Direct damages awarded and appealed, value	$ 718
Punitive damages awarded and appealed, value	$ 718
Putative Securities Class Action
Loss Contingencies
Claims asserted by the company after investigation \| claim						0
Number of current executives named as defendants \| defendant		2
Number of former executives named as defendants \| defendant		2
Brazil Tax Matters
Loss Contingencies
Damages sought, value						$ 400
Minimum
Loss Contingencies
Clients' presence in number of countries \| country						175
Minimum \| IBM v. GF
Loss Contingencies
Damages sought, value			$ 1,500