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Stockholders' Equity - Outstanding Warrants from the January 2020 Equity Offering (Details) - $ / shares | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2022 | Mar. 31, 2021 | Jun. 30, 2021 | Jan. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Warrants issued (in shares) | 229,414 | 310,860 |  |
January 2020 Equity Offering |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Warrants issued (in shares) | 229,414 | 310,860 |  |
Exercise price of common stock (USD per share) | $ 3.67 | $ 3.59 |  |
Investor Warrants |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Warrants issued (in shares) | 187,734 | 269,180 |  |
Sale of common stock (USD per share) |  |  | $ 5.05 |
Exercise price of common stock (USD per share) |  |  |  | $ 3.37
January 2020 Institutional Investor |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Sale of common stock (USD per share) |  |  |  | 3.3700
January 2020 Equity Offering, Private Placement |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Warrants issued (in shares) | 41,680 | 41,680 |  |
Exercise price of common stock (USD per share) |  |  |  | $ 4.9940

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- Definition Exercise price per share or per unit of warrants or rights outstanding. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644 + Details
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