Collateral Account Term

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.

+ Details

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- Definition

Quoted market yields.

+ 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 2021-01-01
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-URIDate 2021-03-24

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- Definition

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

+ References

+ Details

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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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+ Details

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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: Contingent liabilities [member]; Financial assets]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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+ Details

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Balance Type:	debit
Period Type:	instant

- 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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+ Details

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Balance Type:	credit
Period Type:	instant

- 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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Period Type:	duration

- 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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+ Details

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- Definition

The amount of guarantees or collateral provided by the entity in related party transactions. [Refer: Guarantees [member]; Related parties [member]]

+ References

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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

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Financial instruments (Narrative) (Details)	12 Months Ended
Financial instruments (Narrative) (Details)	Dec. 31, 2022 CAD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 CAD ($)	Dec. 31, 2020 CAD ($)
Disclosure of detailed information about financial instruments [line items]
Gain (loss)	$ (72,949,000)		$ 12,529,000
Cash and cash equivalents	1,143,674,000		1,247,447,000	$ 918,382,000
Short-term investments	1,138,174,000		$ 84,906,000
Pledged cash as security	$ 239,000,000
Collateral account term	5 years	5 years
Bottom of range [member]
Disclosure of detailed information about financial instruments [line items]
Quoted market yields	3.30%	3.30%	1.10%
Top of range [member]
Disclosure of detailed information about financial instruments [line items]
Quoted market yields	4.20%	4.20%	1.70%
Provision of guarantees or collateral by entity related party transactions	$ 179,700,000	$ 132,600,000
Interest rate contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Gain (loss)	(6,589,000)		$ (673,000)
Credit risk [member]
Disclosure of detailed information about financial instruments [line items]
Cash and cash equivalents	1,143,674,000		1,247,447,000
Short-term investments	$ 1,138,174,000		$ 84,906,000
Interest rate risk [member]
Disclosure of detailed information about financial instruments [line items]
Proportion of outstanding debt that carries fixed rate	92.00%	92.00%	92.00%
Interest rate risk [member] \| Interest rate contracts [Member]
Disclosure of detailed information about financial instruments [line items]
Percentage increase in interest rate	1.00%	1.00%
Gain (loss)	$ (766,000)
Fair value of Cameco's interest rate swap net liability	7,284,000		$ 673,000
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 three-month Canada Dealer Offered Rate	the three-month Canada Dealer Offered Rate
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]
Margin rate	2.95%