Summary of Significant Accounting Policies - Summary of Cash Equivalents Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Dec. 31, 2015
Dec. 31, 2014
Cash and Cash Equivalents [Line Items]    
Cash and cash equivalents, fair value $ 25,764 $ 49,750
Money Market [Member]    
Cash and Cash Equivalents [Line Items]    
Cash and cash equivalents, fair value 25,764 49,750
Quoted Prices in Active Markets (Level 1) [Member]    
Cash and Cash Equivalents [Line Items]    
Cash and cash equivalents, fair value 25,764 49,750
Quoted Prices in Active Markets (Level 1) [Member] | Money Market [Member]    
Cash and Cash Equivalents [Line Items]    
Cash and cash equivalents, fair value $ 25,764 $ 49,750