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Environmental Remediation Charge

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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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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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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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The carrying amount of the contractual right to receive fees, as compensation in exchange for providing a guarantee to a third party, over life of the guarantee.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount awarded to other party in judgment or settlement of litigation.

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Cash outflows made during the period for environmental remediation activities.

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Commitments and Contingent Liabilities (Additional Information) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) Location	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Location	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jun. 30, 2010 Location	Jun. 30, 2009 Location
Commitments and Contingencies Disclosure [Line Items]
Litigation Settlement, Amount Awarded to Other Party			$ 25
Reserves for environmental contingencies	$ 289		289		$ 304
Reserves for environmental contingencies classified as current liabilities	81		81		62
Environmental remediation charge	6	$ 24	21	$ 75
Payments for Environmental Liabilities	15	21	52	57
Environmental remediation charges	0	$ 21	12	$ 61
Outstanding letters of credit	137		137
Guarantees	9		9
Minimum [Member]
Commitments and Contingencies Disclosure [Line Items]
Unreserved loss contingencies related to environmental matters			100
Maximum [Member]
Commitments and Contingencies Disclosure [Line Items]
Unreserved loss contingencies related to environmental matters			200
Jersey City Manufacturing Plant [Member]
Commitments and Contingencies Disclosure [Line Items]
Reserves for environmental contingencies	99		99		134
Legacy Glass and Chemical Sites [Member]
Commitments and Contingencies Disclosure [Line Items]
Reserves for environmental contingencies	99		99		96
Other Environmental Contingencies [Member]
Commitments and Contingencies Disclosure [Line Items]
Reserves for environmental contingencies	$ 91		$ 91		$ 74
Judicial Consent Order [Member]
Commitments and Contingencies Disclosure [Line Items]
Total number of sites to be remediated \| Location	14		14			20	19
Excavation of Soil [Member]
Commitments and Contingencies Disclosure [Line Items]
Percentage of the total remaining reserve	20.00%		20.00%
Soil Treatment, Transportation And Disposal Of Excavated Soil [Member]
Commitments and Contingencies Disclosure [Line Items]
Percentage of the total remaining reserve	15.00%		15.00%
Construction Services (Related To Soil Excavation, Groundwater Management And Site Security) [Member]
Commitments and Contingencies Disclosure [Line Items]
Percentage of the total remaining reserve	37.00%		37.00%