Income Taxes - Additional Information (Detail) $ in Millions |
3 Months Ended |
|---|---|
|
Mar. 31, 2018
USD ($)
| |
| Income Tax Disclosure [Abstract] | |
| Reserve for uncertain tax positions | $ 6.8 |
| Uncertain tax position reduction in deferred tax assets | 4.6 |
| Uncertain tax positions long term liabilities | 2.2 |
| Tax cuts and jobs act, incomplete accounting, transition tax for accumulated foreign earnings, provisional income tax expense | 0.2 |
| Deemed repatriation of foreign earnings | $ 0.0 |