Fair Value Measurement of Financial Assets and Liabilities - Additional Information (Detail) - USD ($) |
Jun. 30, 2015 |
Dec. 31, 2014 |
|---|---|---|
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Financial Assets measured at fair value on a recurring basis | $ 0 | $ 0 |
| Financial Liabilities measured at fair value on a recurring basis | $ 0 | $ 0 |