High estimate of anticipated cash outlays for environmental remediation costs.

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Low estimate of anticipated cash outlays for environmental remediation costs.

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Environmental Matters [Abstract]

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Historical Environmental Remediation Expense, Lower Limit

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Historical Environmental Remediation Expense, Upper Limit

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Total number of PPG sites to be remediated under the 1990 administrative consent order.

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Percentage Of Total Remaining Reserve

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Remediation Period

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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Carrying value of the obligation (known or estimated) arising from requirements to perform activities to remediate one or more sites, payable in twelve months or in the next operating cycle if longer.

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Estimate of reasonably possible loss exposure in excess of amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.

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Cash outflows made during the period for environmental remediation activities.

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Commitments and Contingent Liabilities (Additional Information - Environmental Matters) (Detail) $ in Millions	12 Months Ended				48 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) Location	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2024 USD ($)	Jun. 30, 2010 Location	Dec. 31, 2009 Location
Environmental Matters [Abstract]
Reserves for environmental contingencies		$ 300	$ 304
Reserves for environmental contingencies classified as current liabilities		99	62
Pretax charges for environmental remediation costs		38	77	$ 78
Cash outlays related to environmental remediation		60	77	64
Historical low end of range of annual environmental remediation expense over the past 15 years		5
Historical high end of range of annual environmental remediation expense over the past 15 years		$ 35
Remediation Period		10 years
Scenario, Forecast \| Maximum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies High Estimate	$ 100				$ 50
Unreserved loss contingencies related to environmental matters, high estimate	200
Scenario, Forecast \| Minimum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies Low Estimate	80				$ 20
Unreserved loss contingencies related to environmental matters, high estimate	$ 100
Excavation of Soil
Environmental Matters [Abstract]
Percentage of the total remaining reserve		21.00%
Soil Treatment Transportation And Disposal Of Excavated Soil
Environmental Matters [Abstract]
Percentage of the total remaining reserve		16.00%
Construction Services
Environmental Matters [Abstract]
Percentage of the total remaining reserve		35.00%
Jersey City Manufacturing Plant
Environmental Matters [Abstract]
Reserves for environmental contingencies		$ 102	134
Pretax charges for environmental remediation costs		15	43	62
Glass and Chemical Sites
Environmental Matters [Abstract]
Reserves for environmental contingencies		106	96
Pretax charges for environmental remediation costs		15	12	8
Other Environmental Contingencies
Environmental Matters [Abstract]
Reserves for environmental contingencies		92	74
Pretax charges for environmental remediation costs		$ 8	$ 22	$ 8
Judicial Consent Order
Environmental Matters [Abstract]
Number Of Sites Involved For Environmental Remediation \| Location		14				20	19