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MANDATORILY REDEEMABLE PREFERRED STOCK - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Aug. 31, 2021 | Mar. 31, 2024 | Dec. 31, 2023 | Mar. 31, 2023 | Dec. 31, 2022 | Mar. 31, 2022 | Dec. 31, 2021
Dividends Payable [Line Items] |  |  |  |  |  |  |
Investment company, cash distributions paid to common stockholders from ordinary income |  |  | 53.20% |  | 61.20% |  | 71.30%
Investment company, cash distributions paid to common stockholders from capital gains |  |  | 46.80% |  | 38.80% |  | 28.70%
Series E Term Preferred Stock |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Preferred stock, dividend rate, percentage | 6.375% |  |  |  |  |  |
Preferred stock, liquidation preference (in USD per share) | $ 25.00 |  |  |  |  |  |
Loss on extinguishment of debt | $ 2.0 |  |  |  |  |  |
4.875% 2028 Notes |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Preferred stock, liquidation preference (in USD per share) |  | $ 25.00 |  | $ 25.00 |  | $ 25.00 |
Notes Payable | 4.875% 2028 Notes |  |  |  |  |  |  |
Dividends Payable [Line Items] |  |  |  |  |  |  |
Interest rate | 4.875% | 4.875% |  | 4.875% |  |  |

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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481139/470-20-50-1B Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 + Details
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