Segmented information (Narrative 1) (Details)	12 Months Ended
Dec. 31, 2024 CAD ($) Item	Dec. 31, 2023 CAD ($)
Disclosure Of Operating Segments [Line Items]
Segment information	Cameco has three reportable segments: uranium, fuel services and Westinghouse. Cameco's reportable segments are strategic business units with different products, processes and marketing strategies.
Number of reportable segments \| Item	3
Uranium [Member]
Disclosure Of Operating Segments [Line Items]
Care and maintenance \| $	$ 51,626,000	$ 50,615,000

The description of the factors used to identify the entity's reportable segments, including the basis of organisation (for example, whether management has chosen to organise the entity around differences in products and services, geographical areas, regulatory environments or a combination of factors and whether operating segments have been aggregated). [Refer: Geographical areas [domain]; Operating segments [member]; Products and services [domain]; Reportable segments [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2024-01-01
-Paragraph 22
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2024-en-r&anchor=para_22_a&doctype=Standard
-URIDate 2024-03-27

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