Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Summary of Cash, Cash Equivalents and Marketable Securities (Detail)

v3.3.0.814
Fair Value Measurements - Summary of Cash, Cash Equivalents and Marketable Securities (Detail) - USD ($)
$ in Thousands
Sep. 30, 2015
Dec. 31, 2014
Sep. 30, 2014
Dec. 31, 2013
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]        
Cash, amortized cost and estimated fair value $ 16,735      
Cash and cash equivalents, amortized cost and estimated fair value 42,477 $ 27,897 $ 48,950 $ 14,593
Restricted cash, amortized cost and estimated fair value 222      
Amortized Cost 23,459      
Gross Unrealized Gains 5      
Gross Unrealized Losses (4)      
Estimated Fair Value 23,460      
Money market securities [Member]        
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]        
Cash equivalents, amortized cost and estimated fair value 25,742      
Restricted cash, amortized cost and estimated fair value 222      
Corporate bonds and commercial paper [Member]        
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]        
Amortized Cost 23,459      
Gross Unrealized Gains 5      
Gross Unrealized Losses (4)      
Estimated Fair Value $ 23,460