This element represents the clients presence in number of countries.

Name:	ibm_ClientsPresenceInNumberOfCountries
Namespace Prefix:	ibm
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	ibm_ContingenciesDisclosureAbstract
Namespace Prefix:	ibm
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the amount of civil penalties chargeable for the Foreign Corrupt Practices Act (FCPA) violations committed.

+ Details

Name:	ibm_LossContingencyLitigationSettlementCivilPenalty
Namespace Prefix:	ibm
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of prejudgment interest, which is included in the total amount of settlement.

+ Details

Name:	ibm_LossContingencyLitigationSettlementPrejudgmentInterest
Namespace Prefix:	ibm
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the amount of profits gained as a result of the conduct alleged in the complaint against the entity, which is included in the total amount of settlement.

+ Details

Name:	ibm_LossContingencyLitigationSettlementProfitsGainedDueToConductAllegedInTheComplaint
Namespace Prefix:	ibm
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The estimated range of reasonably possible losses resulting from an adverse position taken by a taxing authority.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Interpretation (FIN)
-Number 14
-Paragraph 3
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)(3)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

+ Details

Name:	us-gaap_IncomeTaxExaminationRangeOfPossibleLosses
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

This element represents the gross amount awarded, to be received by, or to be remitted to the entity in settlement of litigation occurring during the period.

+ Details

Name:	us-gaap_LitigationSettlementGross
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.

+ Details

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

- Definition

The total amount of pending claims pertaining to a loss contingency accrual as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 5
-Paragraph 9, 10, 11, 12
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

Name:	us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix:	us-gaap
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Contingencies (Details) (USD $) In Millions, unless otherwise specified		1 Months Ended		1 Months Ended
	Jun. 30, 2011	Mar. 31, 2011 ACQIS LLC (Acquis)	Jun. 30, 2011 Former IBM UK Defined Benefit Plan Participants IBM United Kingdom Limited	Mar. 31, 2011 Civil enforcement action with the SEC IBM Korea, LG IBM, IBM (China) Investment Company Limited and IBM Global Services (China) Co., Ltd.
Contingencies
Clients presence in number of countries	170
Loss Contingencies
Amount of settlement		$ 9		$ 10
Claims pending			275
Profits gained as a result of the conduct alleged in the SEC's complaint				5.3
Prejudgment interest				2.7
Civil penalty				2
Income tax examination - Brazil, total potential liability	$ 700