XML 145 R119.htm IDEA: XBRL DOCUMENT
v3.20.4

Segment and Geographic Information - Additional Information (Details) | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 segment | Dec. 31, 2020 USD ($) segment | Dec. 31, 2019 USD ($)
Operating Segments [Abstract] |  |  |
Number of operating segments | 2 |  |
Number of reportable segments |  | 2 |
Borrowings | $ |  | $ 0 | $ 0

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- Definition Number of Operating Segments1 + References No definition available. + Details
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- Definition Number of Reportable Segments + References No definition available. + Details
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Namespace Prefix: | cls_
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Balance Type: | na
Period Type: | duration

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- Definition Operating Segments [Abstract] + References No definition available. + Details
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Namespace Prefix: | cls_
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- Definition The amount of outstanding funds that the entity is obligated to repay. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name IAS -Number 1 -IssueDate 2020-01-01 -Paragraph 55 -URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IAS&num=1&code=ifrs-tx-2020-en-r&anchor=para_55&doctype=Standard -URIDate 2020-01-01 + Details
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Balance Type: | credit
Period Type: | instant