|
Cash Equivalents and Investments - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2015
|
Dec. 31, 2014
|
|
| Cash and Cash Equivalents [Line Items] | ||
| Cash equivalents consisted entirely of money market funds with a fair value | 5.3 | $ 5.1 |
| Maximum [Member] | ||
| Cash and Cash Equivalents [Line Items] | ||
| Long-term investments maturity period, in years | 7 years | |
| Short-Term investments maturity period, in years | 1 year | |
| Minimum [Member] | ||
| Cash and Cash Equivalents [Line Items] | ||
| Long-term investments maturity period, in years | 1 year |