XML 56 R59.htm IDEA: XBRL DOCUMENT v3.19.3
Stockholders' Equity - Common Stock Issuances - Additional Information (Details)
shares in Millions
6 Months Ended
Jun. 30, 2019
shares
Pre-Funded Series D Warrants [Member]  
Stockholders Equity Note [Line Items]  
Exercise of pre-funded Series D Warrants (in shares) 7.9