Number of states examining an entity's unclaimed property records.

No definition available.

Name:	scl_NumberOfStatesInAuditingProcess
Namespace Prefix:	scl_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Life to date payments for environmental remediation response activities.

+ References

No definition available.

+ Details

Name:	scl_PaymentsForSiteContingencies
Namespace Prefix:	scl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Site contingency maximum future response cost percentage.

+ References

No definition available.

+ Details

Name:	scl_SiteContingencyMaximumFutureResponseCostPercentage
Namespace Prefix:	scl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The Increase or Decrease in the accrual for environmental loss in the period from revisions in estimates to existing obligations. The amount does not relate to changes in the environmental accrual related to business acquisitions or divestitures, or to currency movements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 5.Y.Q2)

-URI http://asc.fasb.org/extlink&oid=27011672&loc=d3e149879-122751

+ Details

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

- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The estimated maximum amount of possible loss from the contingency.

+ References

+ Details

Name:	us-gaap_LossContingencyRangeOfPossibleLossMaximum
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The estimated minimum amount of possible loss from the contingency.

+ References

+ Details

Name:	us-gaap_LossContingencyRangeOfPossibleLossMinimum
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The amount of cash paid for the settlement of litigation or for other legal issues during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

+ Details

Name:	us-gaap_PaymentsForLegalSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of payments to settle insured claims and pay costs incurred in the claims settlement process.

+ References

+ Details

Name:	us-gaap_PaymentsForLossesAndLossAdjustmentExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_EnvironmentalRemediationContingencyAxis=scl_MaywoodSiteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_EnvironmentalRemediationContingencyAxis=scl_WilmingtonSiteMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Contingencies - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended		9 Months Ended
Contingencies - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2014 States	Dec. 31, 2013	Sep. 30, 2014
Site Contingency [Line Items]
Environmental and legal losses, minimum	$ 21,900,000	$ 21,900,000
Environmental and legal losses, maximum	41,800,000	41,800,000
Accrued liability for losses	22,000,000	22,000,000	14,700,000
Cash outlays related to legal and environmental matters		1,200,000us-gaap_PaymentsForLegalSettlements	2,400,000us-gaap_PaymentsForLegalSettlements
Accrual for environmental loss contingencies, increase (decrease) for revision in estimates		7,100,000
Number of states examining company unclaimed property records		7scl_NumberOfStatesInAuditingProcess
Liability for unpaid claim and claim adjustment expense, claims paid	3,475,000
Maywood Site [Member]
Site Contingency [Line Items]
Accrual for environmental loss contingencies, increase (decrease) for revision in estimates				7,100,000
Wilmington Site [Member]
Site Contingency [Line Items]
Contribution for future response costs		5.00%
Payment of environmental response costs		$ 2,300,000