Commitments and Contingent Liabilities (Accretion Of Future Funding Obligation) (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) Location
Pittsburgh Corning Corporation | Asbestos Issue
Accretion For Liability Settlement [Line Items]
Accretion of asbestos liability 2013	$ 15
Accretion of asbestos liability 2014	13
Accretion of asbestos liability 2015-2023	39
Accretion of asbestos liability	$ 67
Unfinished Environmental Remediation [Member]
Accretion For Liability Settlement [Line Items]
Number Of Sites Involved For Environmental Remediation | Location	7