Organization and Basis of Presentation - Additional Information (Detail) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026 USD ($)	Jun. 30, 2025 USD ($)	Jun. 30, 2026 USD ($) Location	Jun. 30, 2025 USD ($)
Product Information [Line Items]
Number of business locations \| Location			300
Cost of products	$ 1,064	$ 499	$ 2,054	$ 960
Net income attributable to DNOW Inc.	(21)	14	$ (65)	35
Impairment charge related to operating ROU asset	$ 4
Last-In, First-Out (LIFO) [Member]
Product Information [Line Items]
Cost of products		15		16
Net income attributable to DNOW Inc.		$ (11)		$ (12)

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details