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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2020 | Dec. 31, 2019 | Feb. 28, 2019 | Sep. 30, 2020
Follow-On Equity Offering |  |  |  |
Class of Stock [Line Items] |  |  |  |
Number of shares issued or sold (in shares) |  |  | 5,500,000 |
Sale of stock purchase price (in dollars per share) |  |  | $ 20.00 |
Consideration received on transaction |  |  | $ 118.7 |
Over-allotment option |  |  |  |
Class of Stock [Line Items] |  |  |  |
Number of shares issued or sold (in shares) |  |  | 825,000 |
Sale of stock purchase price (in dollars per share) |  |  | $ 20.00 |
At the Market Offering |  |  |  |
Class of Stock [Line Items] |  |  |  |
Number of shares issued or sold (in shares) |  |  |  | 6,612,815
Sale of stock purchase price (in dollars per share) |  |  |  | $ 26.46
Consideration received on transaction |  |  |  | $ 170.5
Common stock maximum amount available for issuance | $ 175.0 | $ 50.0 |  |

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