XML 20 R17.htm IDEA: XBRL DOCUMENT v3.3.0.814
Stockholders' Equity - Additional Information (Detail) - USD ($)
 1 Months Ended 3 Months Ended
Dec. 31, 2014
Apr. 30, 2014
Sep. 30, 2015
Class of Stock [Line Items]      
Public float maximum market value   $ 75,000,000  
Aggregate value of securities available under shelf registration statement     $ 104,000,000
Series A warrants      
Class of Stock [Line Items]      
Warrants outstanding     215,721
Exercise price     $ 6.00
Warrants expiration date     2016-11
Maximum      
Class of Stock [Line Items]      
Sale of shares and warrants under agreement   $ 150,000,000  
Rights Offering      
Class of Stock [Line Items]      
Warrants outstanding     315,484
Exercise price     $ 7.14
Warrants expiration date     2017-05
Underwritten Registered Offering      
Class of Stock [Line Items]      
Issuance of common stock (in shares) 11,500,000    
Common stock, sales price per share $ 4.00    
Net proceeds from issuance of common stock $ 43,100,000    
Payment of stock offering cost $ 2,900,000    
December 2012 Private Placement      
Class of Stock [Line Items]      
Warrants outstanding     3,230,202
Exercise price     $ 3.12
Warrants expiration date     2017-12