Quarterly report pursuant to Section 13 or 15(d)

Stock Option Plans - Summary of Employee and Nonemployee Stock Option Activity (Detail)

v2.4.0.8
Stock Option Plans - Summary of Employee and Nonemployee Stock Option Activity (Detail) (USD $)
 6 Months Ended 12 Months Ended
Jun. 30, 2014
Dec. 31, 2013
Dec. 31, 2012
Options Outstanding, Number of Shares Outstanding      
Outstanding, beginning balance 873,542 553,340  
Granted 465,000 426,762  
Exercised (29,442) (164)  
Cancelled or expired (31,153) (106,396)  
Outstanding, ending balance 1,277,947 873,542 553,340
Exercisable 457,489    
Options Outstanding, Weighted-Average Exercise Price      
Outstanding, beginning balance $ 10.83 $ 12.76  
Granted $ 15.09 $ 14.57  
Exercised $ 6.65 $ 10.00  
Cancelled or expired $ 9.34 $ 20.46  
Outstanding, ending balance $ 12.52 $ 10.83 $ 12.76
Exercisable $ 8.46    
Weighted-Average Remaining Contractual Term (in years)      
Outstanding 7 years 11 months 9 days 7 years 9 months 7 years 1 month 17 days
Exercisable 5 years 5 months 16 days    
Aggregate Intrinsic Value      
Outstanding, beginning balance $ 3,138,539 $ 1,142,432  
Outstanding, ending balance 1,563,786 3,138,539 1,142,432
Exercisable $ 1,485,305