Revenue (Narrative) (Details) - CAD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Revenue [Abstract]
Revenue From Performance Obligations Satisfied Or Partially Satisfied In Previous Periods		$ 194,000
Explanation Of Effect That Timing Of Satisfaction Of Performance Obligations And Typical Timing Of Payment Have On Contract Assets And Contract Liabilities Explanatory	The revenue related to storage is recognized over time while the revenue related to future uranium and conversion deliveries is expected to be recognized between 2024 and 2030.
Disclosure Of Information About Methods Inputs And Assumptions Used For Determining Transaction Price Explanatory	Cameco’s sales portfolio consists of short and long-term sales commitments. The contracts can be executed well in advance of a delivery and include both fixed and market-related pricing.
Reduction Of Revenue From Performance Obligation	$ 648,000

The reduction of revenue from performance obligations satisfied (or partially satisfied) in previous periods

No definition available.

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- Definition

The disclosure of information about the methods, inputs and assumptions used for determining the transaction price in contracts with customers.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2023-01-01
-Paragraph 126
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2023-en-r&anchor=para_126_a&doctype=Standard
-URIDate 2023-03-23

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- Definition

The explanation of the effect that the timing of satisfaction of performance obligations and the typical timing of payment have on the contract assets and the contract liabilities. [Refer: Performance obligations [member]; Contract assets; Contract liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2023-01-01
-Paragraph 117
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2023-en-r&anchor=para_117&doctype=Standard
-URIDate 2023-03-23

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- References

No definition available.

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- Definition

The amount of revenue from performance obligations satisfied (or partially satisfied) in previous periods. [Refer: Performance obligations [member]; Revenue from contracts with customers]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2023-01-01
-Paragraph 116
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=15&code=ifrs-tx-2023-en-r&anchor=para_116_c&doctype=Standard
-URIDate 2023-03-23

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