Discontinued Operations - Depreciation, Amortization and Capital Expenditures Associated with Discontinued Operations (Detail) - Aromatics [Member] - Discontinued Operations Disposed of by Sale [Member] - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | |||
| Depreciation and amortization | $ 10.8 | $ 14.6 | $ 15.5 |
| Capital expenditures | $ 5.8 | $ 17.4 | $ 18.2 |