Annual report pursuant to Section 13 and 15(d)

The Company - Additional Information (Detail)

v3.8.0.1
The Company - Additional Information (Detail)
12 Months Ended
Jan. 26, 2017
USD ($)
Mar. 11, 2016
Dec. 31, 2017
USD ($)
Segment
Dec. 31, 2016
USD ($)
Dec. 31, 2015
USD ($)
Dec. 31, 2014
USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]            
Number of reportable segments | Segment     1      
Reverse stock split   0.1        
Line of credit facility, maximum borrowing amount $ 50,000,000          
Line of credit facility, maturity date Jan. 26, 2020          
Liquidity     $ 7,400,000 $ 1,900,000    
Cash and cash equivalents     945,000 883,000 $ 219,000 $ 6,033,000
Additional borrowing capacity under the Revolving Credit Facility     6,500,000 1,000,000    
Working capital     $ 34,300,000 $ 51,300,000