Collateral Account Term

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- Definition

Interest Rate From Short Term Investments

+ References

No definition available.

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- Definition

Percentage change in interest rate.

+ References

No definition available.

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- Definition

Proportion of outstanding debt with fixed rate.

+ References

No definition available.

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- Definition

Quoted market yields.

+ References

No definition available.

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- Definition

Trade Receivable Held As Collateral

+ References

No definition available.

+ Details

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- Definition

The adjustment to the basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IFRS
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-IssueDate 2025-01-01
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-URIDate 2025-03-27

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- Definition

The interest rate on borrowings. [Refer: Borrowings]

+ References

+ Details

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- Definition

The basis (reference rate) used for calculation of the interest rate on borrowings. [Refer: Borrowings]

+ References

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- Definition

The amount of cash on hand and demand deposits, along with short-term, highly liquid investments that are readily convertible to known amounts of cash and that are subject to an insignificant risk of changes in value. [Refer: Cash; Cash equivalents]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-URIDate 2025-03-27

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- Definition

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

+ References

No definition available.

+ Details

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- Definition

The amount of financial assets that the entity has pledged as collateral for liabilities or contingent liabilities, including amounts that have been reclassified in accordance with paragraph 3.2.23(a) of IFRS 9. [Refer: Classes of contingent liabilities [domain]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The fair value of financial liabilities. [Refer: At fair value [member]; Financial liabilities]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The gains (losses) resulting from change in the fair value of derivatives recognised in profit or loss. [Refer: Derivatives [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The nominal or face amount of a financial instrument, used to calculate payments made on that instrument.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of short-term deposits held by the entity that are not classified as cash equivalents. [Refer: Cash equivalents]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount of transfers out of Level 1 and into Level 2 of the fair value hierarchy of assets held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The amount of transfers out of Level 2 and into Level 1 of the fair value hierarchy of assets held at the end of the reporting period. [Refer: Level 1 of fair value hierarchy [member]; Level 2 of fair value hierarchy [member]]

+ References

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Financial instruments and related risk management (Narrative) (Details) - CAD ($)	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	$ 1,114,860,000	$ 600,462,000	$ 566,809,000
Short-term investments	99,603,000	0
Pledged cash as security	$ 295,573,000
Collateral account term	5 years
Trade receivable held as collateral	$ 0
Gains (losses) on derivatives	95,017,000	$ (183,103,000)
Transfers out of Level 1 into Level 2 of fair value hierarchy assets	0
Transfers out of Level 2 into Level 1 of fair value hierarchy assets	$ 0
Bottom of range [Member]
Disclosure of detailed information about financial instruments [line items]
Quoted market yields	2.50%	2.80%
Interest rate from short term investments	2.30%
Top of range [Member]
Disclosure of detailed information about financial instruments [line items]
Quoted market yields	3.70%	3.30%
Interest rate from short term investments	2.50%
Interest rate contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Gains (losses) on derivatives	$ 179,000	$ (115,000)
Credit risk [Member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	1,114,860,000	600,462,000
Short-term investments	$ 99,603,000	$ 0
Interest rate risk [Member]
Disclosure of detailed information about financial instruments [line items]
Percentage increase in interest rate	1.00%
Gains (losses) on derivatives	$ (757,000)
Interest rate risk [Member] \| Interest rate contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Proportion of outstanding debt that carries fixed rate	92.00%	72.00%
Fair value of Cameco's interest rate swap net liability	$ 1,677,000	$ 3,172,000
Interest rate risk [Member] \| Interest rate contracts [Member] \| Series H Senior Unsecured Debenture [Member]
Disclosure of detailed information about financial instruments [line items]
Notional amount	$ 75,000,000
Interest rate risk [Member] \| Interest rate contracts [Member] \| Series H Senior Unsecured Debenture [Member] \| Floating interest rate [Member]
Disclosure of detailed information about financial instruments [line items]
Interest rate basis	the daily Canada Overnight Repo Rate Average
Margin rate	1.30%
Interest rate risk [Member] \| Interest rate contracts [Member] \| Series H Senior Unsecured Debenture [Member] \| Fixed interest rate [Member]
Disclosure of detailed information about financial instruments [line items]
Interest rate	2.95%