Segment, Other Supplemental Information and Concentrations - Schedule of Revenue by Geographic Area (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 1,663	$ 1,750	$ 1,833
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	829	894	973
International
Revenues from External Customers and Long-Lived Assets [Line Items]
Total revenue	$ 834	$ 856	$ 860

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

TERADATA CORP /DE/ 10-K