Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)

v2.4.1.9
Stock-based Compensation - Schedule of Weighted-Average Assumptions Used for Calculating Value of Options Granted (Detail)
3 Months Ended
Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]  
Dividend yield 0.00%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate
Expected volatility 75.10%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate
Weighted average risk-free interest rate 1.66%us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate
Expected term 5 years 9 months 18 days