Acquired Intangible Assets - Gross Carrying Amount and Accumulated Amortization for Teradata Acquired Intangible Assets (Detail) - Intellectual property/developed technology - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	$ 35	$ 43
Accumulated Amortization and Currency Translation Adjustments	$ (18)	$ (20)
Minimum
Acquired Finite-Lived Intangible Assets
Amortization Life (in Years)	3 years
Maximum
Acquired Finite-Lived Intangible Assets
Amortization Life (in Years)	5 years

Finite Lived Intangible Assets Accumulated Amortization And Currency Translation Adjustment

No definition available.

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- 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

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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