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Capital Stock - ATM Agreements (Details) - USD ($) $ in Millions |  |  |  | 26 Months Ended | 57 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 05, 2021 | Mar. 10, 2021 | Dec. 18, 2018 | Sep. 30, 2023 | Sep. 30, 2023
2018 Common Stock ATM Agreement | Common Stock |  |  |  |  |
Sale of stock |  |  |  |  |
Maximum amount of shares to be issued |  | $ 50.0 | $ 30.0 |  |
Shares issued (in shares) |  |  |  |  | 0
2018 Common Stock ATM Agreement | Common Stock | Maximum |  |  |  |  |
Sale of stock |  |  |  |  |
Sales commission paid per transaction (as a percent) |  |  | 3.00% |  |
2021 ATM Agreement | Series B Depositary Shares |  |  |  |  |
Sale of stock |  |  |  |  |
Maximum amount of shares to be issued | $ 50.0 |  |  |  |
Shares issued (in shares) |  |  |  | 0 |
2021 ATM Agreement | Series B Depositary Shares | Maximum |  |  |  |  |
Sale of stock |  |  |  |  |
Sales commission paid per transaction, preferred stock (as a percent) | 3.00% |  |  |  |

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