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Segmented information - Narrative (Details) - CAD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Disclosure Of Operating Segments [Abstract] |  |
Segment information | Cameco now has two reportable segments: uranium and fuel services. Cameco's reportable segments are strategic business units with different products, processes and marketing strategies. |
Care and maintenance | $ 212,511,000 | $ 38,311,000
Severance costs | $ 32,111,000 | $ 1,200,000

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- Definition Costs directly expense to cost of sales that are incurred to maintain production facilities during suspension of production. + References No definition available. + Details
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- Definition Compensation an employer provides to an employee who has been laid off, whose job has been eliminated, who has decided to leave the company through mutual agreement, or who has parted ways with the company for other reasons. Costs are directly expensed through cost of sales. + References No definition available. + Details
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Balance Type: | debit
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- Definition 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 [member]; Operating segments [member]; Products and services [member]; Reportable segments [member]] + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name IFRS -Number 8 -IssueDate 2018-01-01 -Paragraph 22 -Subparagraph a -URI http://eifrs.ifrs.org/eifrs/XBRL?type=IFRS&num=8&date=2018-03-01&anchor=para_22_a&doctype=Standard -URIDate 2018-03-16 + Details
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