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

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Forward Contract Indexed to Issuers Equity, Change In Fair Value Of Contract

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Long Term Obligations Reclassified as Short Term Obligations

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The number of Loss Contingency Claims pertaining to asbestos that are currently being Litigated.

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The number of claims in the process of being settled or otherwise resolved.

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Loss Contingency the Number of Claims not in the Process of Being Settled or otherwise resolved. A portion of these claims are being litigated.

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- Definition

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

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No definition available.

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

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No definition available.

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Premises Claims Percentage

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The number of sewer sites. Responsibility for remedial activity at these sites is shared among multiple parties.

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Low-end estimate of the reasonably possible loss exposure in excess of the 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Section S99
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-Number Topic 5
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 450
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Number of claims settled.

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Number of plaintiffs that have filed claims pertaining to a loss contingency.

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Commitments and Contingent Liabilities (Litigation Settlements Disclosure) (Detail) $ in Millions	12 Months Ended			108 Months Ended
	Dec. 31, 2015 USD ($) Location LegalMatter sites	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2014 USD ($) LegalMatter
Unreserved loss contingencies related to environmental matters, low estimate	$ 75
Change in fair value:
Sewer Sites - Responsibility for Remedial Activity is Shared \| sites	10
Asbestos Issue
Loss Contingency Claims Settled Number \| LegalMatter				580
Loss Contingency, Number of Plaintiffs \| LegalMatter				255
Change in fair value:
Loss Contingency Claims in the Process of Being Settled \| LegalMatter				45
Loss Contingency Number of Claims not in the Process of Being Settled. \| LegalMatter				210
Loss Contingency Claims Being Litigated. \| LegalMatter	115
Asbestos Settlement Liability, Current
Beginning balance/Prior year activity	$ 821	$ 763	$ 683
Change in fair value:
PPG stock	(46)	58	75
Equity forward instrument	0
Accretion of asbestos liability	14
Reclassification	7		5
Ending balance/Activity during year	796	821	763	$ 821
Asbestos Settlement Liability, Long-term
Beginning balance/Prior year activity	259	245	237
Change in fair value:
PPG stock	$ 0
Equity forward instrument
Accretion of asbestos liability	$ 0	14	13
Reclassification	(7)		(5)
Ending balance/Activity during year	252	259	245	259
Equity Forward (Asset) Liability
Beginning balance/Prior year activity	(267)	(207)	(130)
Change in fair value:
PPG stock	0
Equity forward instrument	44	(60)	(77)
Accretion of asbestos liability	0
Reclassification	0
Ending balance/Activity during year	(223)	(267)	(207)	(267)
pre-tax Charge
Beginning balance/Prior year activity	12	11	12
Change in fair value:
PPG stock	(46)	58	75
Equity forward instrument	44	(60)	(77)
Accretion of asbestos liability	14	14	13
Reclassification	0
Ending balance/Activity during year	$ 12	$ 12	$ 11	$ 12
Maximum \| Asbestos Issue
Premises Claims Percentage	2.00%
Unfinished Environmental Remediation [Member]
Number Of Sites Involved For Environmental Remediation \| Location	7
Unfinished Environmental Remediation [Member] \| New Jersey Remediation Sites [Member]
Number Of Sites Involved For Environmental Remediation	8