Restructuring and Divestiture Costs - Chlorovinyls - Additional Information (Detail) - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Chlorovinyls [Member] | ||
| Restructuring Cost and Reserve [Line Items] | ||
| Divestiture and long-lived asset impairment charges | $ 0.4 | $ 12.5 |