Debt - Narrative (Details) - USD ($)	Jul. 19, 2018	Feb. 27, 2018
Line of Credit \| May 2016 Credit Agreement
Debt Instrument [Line Items]
Term of credit agreement		5 years
Increase in aggregate availability of credit facility		$ 250,000,000
Aggregate availability of credit facility		$ 750,000,000
Line of Credit \| New Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Term of credit agreement	5 years
Aggregate availability of credit facility	$ 2,000,000,000
Aggregate availability of credit facility after option exercise	2,750,000,000
Letter of Credit \| New Credit Agreement \| Subsequent Event
Debt Instrument [Line Items]
Aggregate availability of credit facility	$ 250,000,000

Line Of Credit Facility, Additional Borrowing Capacity Authorized

No definition available.

Name:	shw_LineOfCreditFacilityAdditionalBorrowingCapacityAuthorized
Namespace Prefix:	shw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility, Maximum Borrowing Capacity After Option Exercises

+ References

No definition available.

+ Details

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Namespace Prefix:	shw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
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- Details

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Data Type:	na
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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: