Entity Tax Identification and Plan Number

No definition available.

Name:	slgn_EntityTaxIdentificationAndPlanNumber
Namespace Prefix:	slgn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Multi employer Plans Status Funded Percentage

+ References

No definition available.

+ Details

Name:	slgn_MultiEmployerPlansStatusFundedPercentage
Namespace Prefix:	slgn_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Proceeds From Taxpayer Assistance, American Rescue Plan Act

+ References

No definition available.

+ Details

Name:	slgn_ProceedsFromTaxpayerAssistanceAmericanRescuePlanAct
Namespace Prefix:	slgn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

Name:	us-gaap_DefinedBenefitPlanDisclosureLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480547/715-80-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 35
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480606/715-80-35-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-11

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 80
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480576/715-80-50-9

+ Details

Name:	us-gaap_MultiemployerPlanEmployerContributionCost
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

+ References

+ Details

Name:	us-gaap_MultiemployerPlanPensionSignificantCertifiedZoneStatusFixedList
Namespace Prefix:	us-gaap_
Data Type:	us-types:zoneStatusItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

+ References

+ Details

Name:	us-gaap_MultiemployerPlanPensionSignificantFundingImprovementOrRehabilitationPlanImplementationStatusFixedList
Namespace Prefix:	us-gaap_
Data Type:	us-types:fundingImprovementAndRehabilitationPlanItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

+ References

+ Details

Name:	us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList
Namespace Prefix:	us-gaap_
Data Type:	us-types:surchargeItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_RetirementPlanNameAxis=slgn_UnitedFoodAndCommercialWorkersLocalOnePensionFundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanNameAxis=slgn_IAMNationalPensionFundMemberMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanNameAxis=slgn_WesternConferenceOfTeamstersPensionPlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

RETIREMENT BENEFITS - Multiemployer Pension Plans (Details) - USD ($) $ in Thousands	12 Months Ended			12001 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Aug. 31, 2023	Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items]
Contributions	$ 3,634	$ 3,558	$ 3,918
Proceeds from taxpayer assistance, American Rescue Plan Act				$ 788,000
United Food and Commercial Workers Local One Pension Fund
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	16-6144007/001
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions	$ 0	$ 141	282
Surcharge Imposed	No
IAM National Pension Fund
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	51-6031295/002
Pension Protection Act Zone Status	Red	Red
FIP / RP Status Pending / Implemented	Implemented
Contributions	$ 2,626	$ 2,511	$ 2,767
Surcharge Imposed	No
Multiemployer funded status		87.00%	84.00%		85.00%
Western Conference of Teamsters Pension Plan
Defined Benefit Plan Disclosure [Line Items]
EIN/Pension Plan Number	91-6145047/001
Pension Protection Act Zone Status	Green	Green
FIP / RP Status Pending / Implemented	NA
Contributions	$ 1,008	$ 906	$ 869
Surcharge Imposed	No