PPG's share of undistributed net earnings of equity affiliates.

No definition available.

Name:	ppg_EquityInUndistributedEarningsLossesOfSubsidiaries
Namespace Prefix:	ppg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage Of Ownership Interests

+ References

No definition available.

+ Details

Name:	ppg_PercentageOfOwnershipInterests
Namespace Prefix:	ppg_
Data Type:	dtr-types1:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(12))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

Dividends received on equity and other investments during the current period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 16
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-16

+ Details

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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

No definition available.

+ Details

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

- Details

Name:	us-gaap_InvestmentTypeAxis=ppg_InvestmentsInAndAdvancesToAffiliatesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=ppg_MarketableSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=ppg_TradingSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_OtherInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=ppg_InvestmentsInOtherOperatingJointVenturesMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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- Details

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Investments (Detail) - USD ($) $ in Millions	12 Months Ended
Investments (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt and Equity Securities, FV-NI [Line Items]
Investments	$ 259	$ 244
Equity in undistributed earnings losses of subsidiaries	21	25	$ 15
Proceeds from dividends received	17	17	$ 9
Investments in equity affiliates
Debt and Equity Securities, FV-NI [Line Items]
Investments	141	134
Marketable equity securities (See Note 11) \| Trading Securities
Debt and Equity Securities, FV-NI [Line Items]
Investments	74	61
Other
Debt and Equity Securities, FV-NI [Line Items]
Investments	$ 44	$ 49
Investments In Other Operating Joint Venture \| Minimum
Debt and Equity Securities, FV-NI [Line Items]
Percentage of ownership interests	20.00%
Investments In Other Operating Joint Venture \| Maximum
Debt and Equity Securities, FV-NI [Line Items]
Percentage of ownership interests	50.00%