Commitments and Contingent Liabilities (Impact of PPG Settlement Arrangement Including Change in Fair Value of Stock to be Transferred) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Change in fair value:
PPG stock	$ (18)	$ 29	$ 10	$ 45
Equity forward instrument	18	(29)	(11)	(46)
Accretion of asbestos liability	3	3	10	10
Asbestos settlement - net expense	$ 3	$ 3	$ 9	$ 9

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Fair value of the PPG stock to be contributed to the Asbestos Trust.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

This element represents the expenses incurred by the entity which are directly related to litigation reserves or settlements.

+ References

No definition available.

+ Details

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- Definition

Amount recognized for the passage of time, typically for liabilities, that have been discounted to their net present values. Excludes accretion associated with asset retirement obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 410

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 420

-SubTopic 10

-Section 35

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6394232&loc=d3e17558-110866

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