Goodwill and Intangible Assets - Assumptions for Our Annual Impairment Assessments of Goodwill (Details)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate (percentage)	2.00%
Term used to extrapolate cash flow projections (in years)	5 years
Capital Equipment CGU
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate (percentage)	9.00%	10.00%	13.00%
Term used to extrapolate cash flow projections (in years)	5 years	5 years	5 years
Discount rate (percentage)	14.00%	11.00%	12.00%
Pre-tax discount rate (percentage)	18.00%
A&D CGU(iii)
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate (percentage)	12.00%	11.00%	8.00%
Term used to extrapolate cash flow projections (in years)	5 years	5 years	5 years
Discount rate (percentage)	12.00%	11.00%	11.00%
Pre-tax discount rate (percentage)	15.00%
Atrenne CGU(iii)
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate (percentage)		19.00%	9.00%
Term used to extrapolate cash flow projections (in years)		5 years	5 years
Discount rate (percentage)		10.00%	10.00%
PCI CGU
Disclosure of information for cash-generating units [line items]
Annual revenue growth rate (percentage)	11.00%	9.00%
Term used to extrapolate cash flow projections (in years)	5 years	5 years
Discount rate (percentage)	15.00%	15.00%
Pre-tax discount rate (percentage)	18.00%

Growth Rate Used To Extrapolate Cash Flow Projections, Term

No definition available.

Name:	cls_GrowthRateUsedToExtrapolateCashFlowProjectionsTerm
Namespace Prefix:	cls_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Pre-Tax Discount Rate Applied To Cash Flow Projections

+ References

No definition available.

+ Details

Name:	cls_PreTaxDiscountRateAppliedToCashFlowProjections
Namespace Prefix:	cls_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The discount rate applied to cash flow projections for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2022-03-24
-Paragraph 134
-Subparagraph d
-Clause v
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2022-en-r&anchor=para_134_d_v&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2022-03-24
-Paragraph 134
-Subparagraph e
-Clause v
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2022-en-r&anchor=para_134_e_v&doctype=Standard
-URIDate 2022-03-24

+ Details

Name:	ifrs-full_DescriptionOfDiscountRatesAppliedToCashFlowProjections
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The growth rate used to extrapolate cash flow projections beyond the period covered by the most recent budgets/forecasts for a cash-generating unit (group of units). [Refer: Cash-generating units [member]]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2022-03-24
-Paragraph 134
-Subparagraph d
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2022-en-r&anchor=para_134_d_iv&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 36
-IssueDate 2022-03-24
-Paragraph 134
-Subparagraph e
-Clause iv
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=36&code=ifrs-tx-2022-en-r&anchor=para_134_e_iv&doctype=Standard
-URIDate 2022-03-24

+ Details

Name:	ifrs-full_DescriptionOfGrowthRateUsedToExtrapolateCashFlowProjections
Namespace Prefix:	ifrs-full_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	ifrs-full_DisclosureOfInformationForIndividualAssetOrCashgeneratingUnitWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesLineItems
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	ifrs-full_IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesAxis=cls_CapitalEquipmentCGUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesAxis=cls_ADCGUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesAxis=cls_AtrenneCGUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	ifrs-full_IndividualAssetsOrCashgeneratingUnitsWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesAxis=cls_PCICGUMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: