Earnings Per Common Share (Calculations) (Details) shares in Millions |
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2016
shares
|
Mar. 31, 2015
shares
|
|
| Earnings Per Share [Abstract] | ||
| Stock Split, Conversion Ratio | 2 | |
| Earnings per common share - assuming dilution (attributable to PPG) | ||
| Weighted average common shares outstanding | 267.6 | 273.2 |
| Effect of dilutive securities: | ||
| Stock options | 0.9 | 1.2 |
| Other stock compensation plans | 0.9 | 1.2 |
| Potentially dilutive common shares | 1.8 | 2.4 |
| Adjusted weighted average common shares outstanding | 269.4 | 275.6 |
| Outstanding stock options excluded from the computation of diluted earnings per share due to their antidilutive effect | 0.6 | 0.0 |