Employee Stock-based Compensation Plans Composition of Teradata Restricted Stock Grants (Detail) shares in Thousands	12 Months Ended
Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares \| shares	2,118
Weighted-average fair value of restricted shares units granted (in usd per share) \| $ / shares	$ 32.82
Service-based shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares \| shares	2,055
Weighted-average fair value of restricted shares units granted (in usd per share) \| $ / shares	$ 32.68
Performance-based shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares \| shares	63
Weighted-average fair value of restricted shares units granted (in usd per share) \| $ / shares	$ 37.36

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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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.

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