Annual report pursuant to Section 13 and 15(d)

Income Taxes - Additional Information (Detail)

v3.7.0.1
Income Taxes - Additional Information (Detail) - USD ($)
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Income Tax Disclosure [Line Items]    
Valuation allowance $ (54,310,000) $ (49,514,000)
Net operating loss carryforwards federal 124,000,000  
Net operating loss carryforwards state 75,200,000  
Cumulative unrealized excess tax deductions 7,100,000 6,900,000
Undistributed earnings from foreign subsidiaries $ 0 $ 0
Minimum    
Income Tax Disclosure [Line Items]    
Operating loss carryforwards, expiration period 2019  
Maximum    
Income Tax Disclosure [Line Items]    
Operating loss carryforwards, expiration period 2036  
Federal    
Income Tax Disclosure [Line Items]    
Research and development tax credit carryforwards $ 1,500,000  
Federal | Minimum    
Income Tax Disclosure [Line Items]    
Research and development tax credit carryforwards, expiration period 2019  
Federal | Maximum    
Income Tax Disclosure [Line Items]    
Research and development tax credit carryforwards, expiration period 2036  
State | Indefinite Life    
Income Tax Disclosure [Line Items]    
Research and development tax credit carryforwards $ 1,200,000