Common Stock and Preferred Stock (Converted into Common Stock) - Shares Reserved for Future Issuance (Details)	Sep. 30, 2020 shares
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	2,038,195
Outstanding stock options
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	969,822
2014 Equity Incentive Plan | Common stock options available for future grant:
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	43,311
2017 Inducement Equity Incentive Plan | Common stock options available for future grant:
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	46,250
2019 Omnibus Equity Incentive Plan | Common stock options available for future grant:
Class of Stock [Line Items]
Total common shares reserved for future issuance (in shares)	978,812