Quarterly report pursuant to Section 13 or 15(d)

Stock Options - Summary of Option Activity (Detail)

v2.4.1.9
Stock Options - Summary of Option Activity (Detail) (USD $)
3 Months Ended
Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Shares Outstanding, Beginning balance 3,556,691us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Shares, Granted 145,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross
Shares, Exercised (2,843)us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
Shares Outstanding, Ending balance 3,698,848us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Shares, Vested 817,015us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares
Weighted Average Exercise Price Outstanding, Beginning balance $ 0.83us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Weighted Average Exercise Price, Granted $ 2.78us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice
Weighted Average Exercise Price, Exercised $ 0.17us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice
Weighted Average Exercise Price Outstanding, Ending balance $ 0.91us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice
Weighted Average Exercise Price, Vested $ 0.43us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingWeightedAverageExercisePrice
Weighted Average Remaining Contractual Term Outstanding in Years, Ending balance 8 years 9 months
Weighted Average Remaining Contractual Term in Years, Vested 7 years 1 month 28 days
Average Intrinsic Value, Ending Balance $ 7,057,231us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue
Average Intrinsic Value, Vested $ 1,948,425us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestOutstandingAggregateIntrinsicValue