|
Stockholders' Equity - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2015
|
Mar. 31, 2014
|
|
| Stockholders Equity [Line Items] | ||
| Total unrecognized compensation costs related to non-vested stock options, restricted stock unit awards (RSUs), performance share units (PSUs) and share unit awards | $ 44.9 | |
| Recognition period of unrecognized compensation costs | 1 year 10 months 24 days | |
| Stock options vested and expected to vest, contractual term | 10 years | |
| Share unit award expense | $ 1.3 | $ 1.1 |
| Minimum [Member] | Restricted Stock Units (RSUs) [Member] | ||
| Stockholders Equity [Line Items] | ||
| Vesting period, year | 1 year | |
| Minimum [Member] | Stock Options [Member] | ||
| Stockholders Equity [Line Items] | ||
| Vesting period, year | 1 year | |
| Maximum [Member] | Restricted Stock Units (RSUs) [Member] | ||
| Stockholders Equity [Line Items] | ||
| Vesting period, year | 3 years | |
| Maximum [Member] | Stock Options [Member] | ||
| Stockholders Equity [Line Items] | ||
| Vesting period, year | 5 years | |