Postretirement Benefit Plans - Defined Contribution Plans - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	$ 11,440,000	$ 10,353,000	$ 10,949,000
Percentage of union and non-union employees eligible for either statutory or Company's sponsored profit sharing contributions	85.00%
Percentage of us based union and non-union employees eligible for either statutory or Company's sponsored profit sharing contributions	100.00%
Statutory Plans [Member]
Defined Contribution Plan Disclosure [Line Items]
Defined contribution plan expense	$ 138,000	298,000	$ 480,000
Defined Contribution Plans [Member]
Defined Contribution Plan Disclosure [Line Items]
Balance of trust assets	$ 276,000	$ 472,000

Balance of the trust assets.

No definition available.

Name:	scl_BalanceOfTrustAssets
Namespace Prefix:	scl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of US based union and non union employees eligible for either Statutory or companys sponsored profit sharing contributions.

+ References

No definition available.

+ Details

Name:	scl_PercentageOfUSBasedUnionAndNonUnionEmployeesEligibleForEitherStatutoryOrCompanysSponsoredProfitSharingContributions
Namespace Prefix:	scl_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of union and non-union employees eligible for either statutory or Company's sponsored profit sharing contributions.

+ References

No definition available.

+ Details

Name:	scl_PercentageOfUnionAndNonUnionEmployeesEligibleForEitherStatutoryOrCompanysSponsoredProfitSharingContributions
Namespace Prefix:	scl_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 70
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480794/715-70-50-1

+ Details

Name:	us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

+ Details

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

- Details

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

- Details

Name:	us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: