Leases - Additional Information (Detail) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Operating Leased Assets [Line Items] | |||
| Rental expense for operating leases | $ 27.9 | $ 27.4 | $ 22.6 |
| Minimum | |||
| Operating Leased Assets [Line Items] | |||
| Operating leases renewal option period | 1 year | ||
| Maximum | |||
| Operating Leased Assets [Line Items] | |||
| Operating leases renewal option period | 10 years | ||