Gross Carrying Amount and Accumulated Amortization for Teradata Acquired Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	$ 246	$ 251
Accumulated Amortization	(75)	(68)
Currency Translation Adjustment	2	3
Intellectual property/developed technology
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	148	153
Accumulated Amortization	(52)	(50)
Currency Translation Adjustment	1	2
Customer relationships
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	77	77
Accumulated Amortization	(18)	(15)
Currency Translation Adjustment	1	1
Trademarks/trade names
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	15	15
Accumulated Amortization	(4)	(2)
Currency Translation Adjustment	0	0
In-process research and development
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	5 years
Gross Carrying Amount	5	5
Accumulated Amortization	0	0
Currency Translation Adjustment	0	0
Non-compete agreements
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	1	1
Accumulated Amortization	(1)	(1)
Currency Translation Adjustment	$ 0	$ 0
Minimum
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	1 year
Minimum | Intellectual property/developed technology
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	1 year
Minimum | Customer relationships
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	3 years
Minimum | Trademarks/trade names
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	3 years 6 months
Minimum | Non-compete agreements
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	2 years
Maximum
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	10 years
Maximum | Intellectual property/developed technology
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	7 years
Maximum | Customer relationships
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	10 years
Maximum | Trademarks/trade names
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	5 years
Maximum | Non-compete agreements
Acquired Finite-Lived Intangible Assets
Original Amortization Life (in Years)	2 years 6 months