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Equity (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020
Class of Stock [Line Items] |  |  |  |  |
Common stock shares authorized under equity program | 500,000,000 | 500,000,000 | 500,000,000 | 500,000,000 | 500,000,000
Net proceeds * |  |  | $ 88,830 | $ 3,410 |
At-the-market offering |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |
Common stock shares authorized under equity program | 6,400,000 |  | 6,400,000 |  |
Common stock shares reserved for future issuance | 3,600,000 |  | 3,600,000 |  |
Shares issued | 1,000,000.0 | 0 | 2,800,000 | 0 |
Net proceeds * | $ 34,200 | $ 0 | $ 88,800 | $ 0 |
Issuance costs | $ 500 | $ 0 | $ 1,200 | $ 0 |

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