Commitments and Contingent Liabilities (Additional Information) (Detail) (USD $)	1 Months Ended	12 Months Ended			3 Months Ended	1 Months Ended		12 Months Ended		36 Months Ended	9 Months Ended	3 Months Ended
	Dec. 31, 2009 LegalMatter	Dec. 31, 2014 sites	Dec. 31, 2013	Dec. 31, 2012	Mar. 31, 2000	Dec. 31, 2008	May 14, 2002	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2019	Sep. 30, 2012	Sep. 30, 2014	Sep. 30, 2013	Mar. 31, 2012	Jul. 31, 2014	Jan. 31, 2000 Plaintiff	Sep. 30, 2008 Location	Dec. 31, 2011 Location
Commitments and Contingencies Disclosure [Line Items]
Interest Penalty Asserted by a Foreign Tax Authority		$ 70,000,000
Asbestos [Abstract]
PPG percent ownership interest															40.00%
Obligation reported as a current liability		821,000,000	763,000,000
Obligation reported as a non-current liability		259,000,000	245,000,000
PC-related claims at trial that PPG was found not responsible	2
Number of plaintiffs one jury found PPG, for the first time, partly responsible for injuries																5
Environmental Matters [Abstract]
Reserves for environmental contingencies		317,000,000	337,000,000
Reserves for environmental contingencies classified as current liabilities		141,000,000	133,000,000
Cash outlays related to environmental remediation		165,000,000	111,000,000	62,000,000
Pretax charges for environmental remediation costs		144,000,000	108,000,000	166,000,000
Historical low end of range of annual environmental remediation expense over the past 15 years		10,000,000
Historical high end of range of annual environmental remediation expense over the past 15 years		30,000,000
Remediation Period		10 years
Sewer Sites - Responsibility for Remedial Activity is Shared		10
Unreserved loss contingencies related to environmental matters, low estimate		75,000,000
Unreserved loss contingencies related to environmental matters, high estimate		200,000,000
Asbestos Issue
Asbestos [Abstract]
Number of pending cases		114,000	114,000
Reduction in cash obligation to the Trust, corresponding increase in reserve for PPG claims responsibility						162,000,000
PPG's reserve for asbestos-related claims that will not be channeled to the Trust		162,000,000	162,000,000
Pittsburgh Corning Corporation
Asbestos [Abstract]
PPG percent ownership interest		50.00%
After-tax charge, write-off of investment in PC, related to PC filing for Chapter 11 Bankruptcy					35,000,000
Number of days after effective date of a confirmed reorganization plan					30 days
Pittsburgh Corning Corporation | Asbestos Issue
Asbestos [Abstract]
Number of days after second amended reorganization plan							30 days
Agreement to convey assets to the PC asbestos settlement trust (the "Trust"), shares of PPG common stock						1,388,889	1,388,889
Future PPG cash payments to the Trust						825,000,000	998,000,000
Fixed payment schedule, period							21 years
Fixed payment schedule, effective date							2003-06-30
Future PPG cash payments to the Trust, prepayment discount rate						5.50%	5.50%
Future PPG legal fees and expenses on behalf of the Trust							30,000,000
Future cash payments to the Trust by PPG's participating historical insurance carriers						1,700,000,000	1,700,000,000
Future cash payments to the Trust by PPG's participating historical insurance carriers, prepayment discount rate						5.50%	5.50%
Total obligation		1,080,000,000	1,008,000,000
Obligation reported as a current liability		821,000,000	763,000,000
Obligation reported as a non-current liability		259,000,000	245,000,000
Accretion of asbestos liability		81,000,000
Scenario, Forecast | Maximum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies High Estimate								80,000,000	150,000,000	45,000,000
Scenario, Forecast | Minimum
Environmental Matters [Abstract]
Cash For Environmental Loss Contingencies Low Estimate								60,000,000	130,000,000	25,000,000
Third Amendment | Pittsburgh Corning Corporation | Asbestos Issue
Asbestos [Abstract]
Period of funding effective period											30 days
Construction Services [Member]
Environmental Matters [Abstract]
Percentage of the total remaining reserve		40.00%
Administrative Content Order Nineteen Ninety Aco [Member]
Environmental Matters [Abstract]
Total number of sites to be remediated		61
Administrative Content Order Nineteen Ninety Aco [Member] | Finished Environmental Remediation [Member]
Environmental Matters [Abstract]
Total number of sites to be remediated		47
Administrative Content Order Nineteen Ninety Aco [Member] | Unfinished Environmental Remediation
Environmental Matters [Abstract]
Total number of sites to be remediated		14
Jersey City Manufacturing Plant
Environmental Matters [Abstract]
Reserves for environmental contingencies		211,000,000	231,000,000
Pretax charges for environmental remediation costs		136,000,000	89,000,000	145,000,000								136,000,000	89,000,000	145,000,000
Orphan Sites Settlement
Environmental Matters [Abstract]
Number of sites		3
Other Contingency Matters [Abstract]
Number of sites		3
Orphan Sites Settlement | Unfinished Environmental Remediation
Environmental Matters [Abstract]
Total number of sites to be remediated																	6
Other Environmental Contingencies [Member]
Environmental Matters [Abstract]
Reserves for environmental contingencies		106,000,000	106,000,000
Pretax charges for environmental remediation costs		$ 8,000,000	$ 19,000,000	$ 21,000,000
Judicial Consent Order [Member]
Environmental Matters [Abstract]
Total number of sites to be remediated		19																20
Soil Treatment Transportation And Disposal Of Excavated Soil [Member]
Environmental Matters [Abstract]
Percentage of the total remaining reserve		30.00%