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 | |
|---|---|---|
Mar. 31, 2016 |
Mar. 31, 2015 |
|
| Change in fair value: | ||
| PPG stock | $ 35 | $ (8) |
| Equity forward instrument | (36) | 7 |
| Accretion of asbestos liability | 4 | 4 |
| Asbestos settlement - net expense | $ 3 | $ 3 |