Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Additional Information (Detail)

v3.19.2
Stockholders' Equity - Additional Information (Detail) - USD ($)
$ in Thousands
 1 Months Ended 3 Months Ended 6 Months Ended
Jun. 06, 2019
Mar. 06, 2019
Sep. 06, 2018
Aug. 21, 2018
Jun. 30, 2019
Mar. 31, 2019
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Dec. 31, 2018
Class of Stock [Line Items]                      
Net proceeds from stock issuance             $ 8,055 $ 32,601 $ 12,215 $ 32,536  
Warrants outstanding         1,297,151   1,297,151   1,297,151   1,297,151
Common Stock and Employee Stock Purchase Plan [Member]                      
Class of Stock [Line Items]                      
Shares issued in connection with stock option exercise                 147,675    
Common Stock [Member]                      
Class of Stock [Line Items]                      
Common stock shares issued             1,006,663 1,955,000 1,668,663 1,955,000  
Net proceeds from stock issuance             $ 1 $ 2 $ 2 $ 2  
Stock issuance costs                 $ 428    
Shares issued in connection with stock option exercise             27,049   47,099    
Common Stock [Member] | Performance Bridge [Member]                      
Class of Stock [Line Items]                      
Business acquisition, shares issued or issuable       349,072         580,713    
Common Stock [Member] | Machine Box, Inc. [Member]                      
Class of Stock [Line Items]                      
Business acquisition, shares issued or issuable 97,082 135,583 128,300                
Business acquisition, additional shares issued or issuable         77,666 108,469     186,135