Commitments and Contingent Liabilities (Accretion Of Future Funding Obligation) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Jun. 09, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Line Items]
Settlement of equity forward instrument with counterparty			$ (49)
Equity Method Investments	$ 21			$ 21
Company Stock To Be Contributed To Asbestos Trust			308
Asbestos settlement	0		0	0			$ 796
Asbestos settlement	0		0	0			252
Change in fair value of PPG Stock			34
Fair value of the equity forward arrangement to mitigate the impact of changes in fair value of stock contributed to the asbestos settlement trust			0			$ 258	$ (223)
Accretion Of Interest On Litigation Settlements			6
Cash Contributed to the PC Trust			(764)
Gain Loss Related To Asbestos Litigation Settlement	$ 0	$ 3	5	5	$ 9
Cash Paid for Asbestos Settlement Funding			(813)	$ (813)	$ 0
Pittsburgh Corning Corporation [Member]
Commitments and Contingencies Disclosure [Line Items]
Equity Method Investments			(15)
Other Noncurrent Liabilities [Member]
Commitments and Contingencies Disclosure [Line Items]
Cash Contributed to the PC Trust			(258)
Other Current Liabilities [Member]
Commitments and Contingencies Disclosure [Line Items]
Cash Contributed to the PC Trust			$ (506)
Asbestos Issue [Member]
Commitments and Contingencies Disclosure [Line Items]
Fair value of the equity forward arrangement to mitigate the impact of changes in fair value of stock contributed to the asbestos settlement trust						$ (35)