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Stockholders' Equity (At-the-Market) (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Aug. 16, 2019 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Class of Stock [Line Items] |  |  |  |
Shares repurchased and retired (in shares) |  | 20,101,494 | 14,085,678 | 0
At The Market |  |  |  |
Class of Stock [Line Items] |  |  |  |
Distribution agreement term | 3 years |  |  |
At-the-market, maximum potential proceeds | $ 400,000 |  |  |
Sales commission, percent of gross sales price | 2.00% |  |  |
Number of shares issued (in shares) |  | 0 | 0 | 1,357,526
Value remaining outstanding for future offerings |  | $ 390,000 |  |
Gross proceeds (usd per share) |  |  |  | $ 7.40
Proceeds from sale of stock |  |  |  | $ 9,900
Debt issuance fees |  |  |  | $ 100

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