Commitments and Contingent Liabilities (Impact of PPG Settlement Arrangement Including Change in Fair Value of Stock to be Transferred) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 09, 2016	Dec. 31, 2015
Asbestos Litigation Reserve Noncurrent	$ 0		$ 0			$ 252
Change in fair value of PPG Stock			34
Forward Contract Indexed To Issuers Equity Fair Value	0		0		$ 258	(223)
Asbestos Litigation Reserve Current	0		0			$ 796
Accretion Of Interest On Litigation Settlements			6
Settlement of equity forward instrument with counterparty			(49)
Equity Method Investments	21		21
Company Stock To Be Contributed To Asbestos Trust			(308)
Cash Contributed to the PC Trust	(764)		$ (764)
Reclassifications [Text Block]			-1
Gain Loss Related To Asbestos Litigation Settlement	(2)	$ (3)	$ (5)	$ (6)
Cash Paid for Asbestos Settlement Funding			813	$ 0
Prepayment discount of future pre-tax cash payments to the trust	61		61
Prepayment of future pre-tax cash payments to the trust	764		764
Pittsburgh Corning Corporation [Member]
Equity Method Investments	(15)		(15)
Other Current Liabilities [Member]
Cash Contributed to the PC Trust	(506)		(506)
Other Noncurrent Liabilities [Member]
Cash Contributed to the PC Trust	$ (258)		$ (258)
Asbestos Issue [Member]
Forward Contract Indexed To Issuers Equity Fair Value					$ (35)