Property, Plant and Equipment - Additional Information (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
|
| Property, Plant and Equipment [Abstract] | ||||
| Depreciation expense related to property, plant and equipment | $ 53.8 | $ 47.5 | $ 107.9 | $ 90.5 |