Interest cost associated with litigation settlements due to recognition of initial liability at net present value.

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Cash Contributed to the PC Trust

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Cash Paid for Asbestos Settlement Funding

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Fair value of the PPG stock to be contributed to the Asbestos Trust.

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Forward Contract Indexed to Issuers Equity, Fair Value

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Long Term Obligations Reclassified as Short Term Obligations

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Change in fair value of PPG stock to be contributed to the Asbestos Trust.

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Difference between the 2nd and 3rd amended PC plan of re-organization in cash to be contributed to the Trust by PPG which has been established as a reserve for asbestos-related claims that will not be channeled to the Trust.

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No definition available.

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Prepayment of future pre-tax cash payments to the trust

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Number of shares of PPG stock to be contributed to the asbestos Trust by PPG upon finalization/approval of the 3rd amended PC plan of re-organization.

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No definition available.

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Discount rate to be applied to any pre-payments made by PPG to the asbestos Trust.

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Settlement of equity forward instrument with counterparty

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No definition available.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount due in settlement of a claim for reimbursement from an insurance company when the Company has suffered a loss covered under an insurance policy.

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No definition available.

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Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

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Number of pending claims pertaining to a loss contingency.

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Commitments and Contingent Liabilities (Litigation Settlements Disclosure) (Detail) claim in Thousands, $ in Millions	1 Months Ended	12 Months Ended
	May 14, 2002 shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2008 USD ($)	Dec. 31, 2000 claim
Forward Contract Indexed To Issuers Equity Fair Value					$ 258
Prepayment of future pre-tax cash payments to the trust					$ 764
Cash Paid for Asbestos Settlement Funding		$ 0	$ 0	$ 813
Change in fair value:
Investment in equity affiliates		(132)	(134)	(46)
Other Reserves		$ 180
Asbestos Issue
Loss Contingency, Pending Claims, Number		460						114
Change in fair value:
Other Reserves		$ 162
Individually Identified Premises Claims
Loss Contingency, Pending Claims, Number \| claim								1
Asbestos Settlement Liability, Current
Beginning balance/Prior year activity				796
Change in fair value:
PPG stock				(34)
Equity forward instrument				0
Accretion of asbestos liability				0
Company Stock To Be Contributed To Asbestos Trust				(308)
Reclassification				1
Asbestos Settlement Liability, Long-term
Beginning balance/Prior year activity				252
Change in fair value:
PPG stock				0
Accretion of asbestos liability				6
Reclassification				0
Equity Forward (Asset) Liability
Forward Contract Indexed To Issuers Equity Fair Value						$ (223)
Change in fair value:
PPG stock				0
Equity forward instrument				35
Accretion of asbestos liability				0
Settlement of equity forward instrument with counterparty				(49)
Company Stock To Be Contributed To Asbestos Trust				(308)
Reclassification				1
Pre-tax Charge
Beginning balance/Prior year activity			$ 5	12
Change in fair value:
PPG stock				(34)
Equity forward instrument				35
Accretion of asbestos liability				6
Reclassification				0
Ending balance/Activity during year				5
Pittsburgh Corning Corporation
Change in fair value:
Investment in equity affiliates				(15)
Other Current Liabilities
Change in fair value:
Cash Contributed to the PC Trust				(506)
Other Noncurrent Liabilities
Change in fair value:
Cash Contributed to the PC Trust				$ (258)
Pittsburgh Corning Corporation
Ownership interest		50.00%
Pittsburgh Corning Corporation \| Asbestos Issue
Agreement to convey assets to the PC asbestos settlement trust (the Trust), shares of PPG common stock \| shares	2,777,778
Change in fair value:
Future cash payments to the Trust by PPG's participating historical insurance carriers							$ 1,700
Future PPG cash payments to the Trust, prepayment discount rate	5.50%