FINANCIAL HIGHLIGHTS (Details) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Sep. 30, 2023 |
Sep. 30, 2022 |
Sep. 30, 2021 |
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2014 |
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| Investment Company, Financial Highlights [Roll Forward] | ||||||||||
| Net asset value at beginning of period / year (in USD per share) | $ 9.08 | $ 9.28 | $ 7.40 | $ 8.22 | $ 8.32 | $ 8.40 | $ 8.62 | $ 9.06 | $ 9.51 | $ 9.81 |
| Income from operations | ||||||||||
| Net investment income (in USD per share) | 1.10 | 0.94 | 0.79 | 0.81 | 0.84 | 0.85 | 0.84 | 0.84 | 0.84 | 0.87 |
| Net realized and unrealized gain (loss) on investments (in USD per share) | 0.03 | (0.35) | 1.79 | (0.84) | (0.15) | (0.16) | (0.12) | (0.35) | (0.50) | (0.23) |
| Net realized and unrealized gain (loss) on other (in USD per share) | 0.01 | (0.01) | (0.04) | (0.03) | (0.01) | 0 | (0.05) | 0 | 0.06 | (0.11) |
| Total from operations (in USD per share) | 1.14 | 0.58 | 2.54 | (0.06) | 0.68 | 0.69 | 0.67 | 0.49 | 0.40 | 0.53 |
| Distributions to common stockholders from | ||||||||||
| Net investment income (in USD per share) | (0.94) | (0.76) | (0.75) | (0.80) | (0.82) | (0.84) | (0.84) | (0.70) | (0.84) | (0.12) |
| Realized gains (in USD per share) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | (0.14) | 0 | 0 |
| Return of capital (in USD per share) | (0.00) | (0.04) | (0.03) | (0.01) | (0.02) | 0 | 0 | 0 | 0 | (0.72) |
| Total distributions (in USD per share) | (0.94) | (0.80) | (0.78) | (0.81) | (0.84) | (0.84) | (0.84) | (0.84) | (0.84) | (0.84) |
| Issuance of common stock (in USD per share) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0.06 | 0 |
| Discounts, commissions, and offering costs (in USD per share) | 0 | 0 | (0.01) | 0 | (0.01) | (0.01) | (0.04) | (0.05) | (0.01) | 0 |
| Repurchase of common stock (in USD per share) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0.02 | 0 | 0 |
| Net anti-dilutive (dilutive) effect of equity offering (in USD per share) | 0.13 | 0.02 | 0.15 | 0.05 | 0.07 | 0.08 | (0.02) | (0.05) | (0.06) | 0 |
| Total capital share transactions (in USD per share) | 0.13 | 0.02 | 0.14 | 0.05 | 0.06 | 0.07 | (0.06) | (0.08) | (0.01) | 0 |
| Other, net (in USD per share) | (0.02) | 0 | (0.02) | 0 | 0 | 0 | 0.01 | (0.01) | 0 | 0.01 |
| Net asset value at end of period / year (in USD per share) | 9.39 | 9.08 | 9.28 | 7.40 | 8.22 | 8.32 | 8.40 | 8.62 | 9.06 | 9.51 |
| Per common share market value at beginning of year (in USD per share) | 8.49 | 11.30 | 7.41 | 9.75 | 9.50 | 9.50 | 8.13 | 8.13 | 8.77 | 8.73 |
| Per common share market value at end of year (in USD per share) | $ 9.64 | $ 8.49 | $ 11.30 | $ 7.41 | $ 9.75 | $ 9.50 | $ 9.50 | $ 8.13 | $ 8.13 | $ 8.77 |
| Total return | 24.85% | (19.16%) | 64.93% | (15.75%) | 12.55% | 9.53% | 27.90% | 11.68% | 2.40% | 9.62% |
| Common stock, shares, outstanding at end of year (in shares) | 43,508,897 | 34,734,796 | 34,304,371 | 31,566,850 | 30,345,923 | 28,501,980 | 26,160,684 | 23,344,422 | 21,131,622 | 21,000,160 |
| Statement of Assets and Liabilities Data: | ||||||||||
| Net assets at end of year | $ 408,695 | $ 315,487 | $ 318,439 | $ 233,743 | $ 249,330 | $ 237,092 | $ 219,650 | $ 201,207 | $ 191,444 | $ 199,660 |
| Average net assets | 349,518 | 320,838 | 275,509 | 235,266 | 239,851 | 234,092 | 215,421 | 193,228 | 198,864 | 201,009 |
| Senior Securities Data: | ||||||||||
| Borrowings under line of credit, at cost | 47,800 | 141,800 | 50,500 | 128,000 | 66,900 | 110,000 | 93,000 | 71,300 | 127,300 | 36,700 |
| Mandatorily redeemable preferred stock | 0 | 0 | 0 | 0 | 51,750 | 51,750 | 51,750 | 61,000 | 61,000 | 61,000 |
| Notes Payable | $ 257,000 | $ 200,000 | $ 188,813 | $ 96,313 | $ 57,500 | $ 0 | $ 0 | $ 0 | $ 0 | $ 0 |
| Ratios/Supplemental Data: | ||||||||||
| Ratio of net expenses to average net assets | 12.99% | 9.62% | 10.04% | 9.69% | 10.61% | 9.61% | 8.26% | 10.16% | 10.24% | 9.06% |
| Ratio of net investment income to average net assets | 11.74% | 10.06% | 9.48% | 10.70% | 10.25% | 9.86% | 9.95% | 10.08% | 8.90% | 9.14% |
| Ratio of expenses to average net assets - annualized | 16.31% | 13.13% | 13.17% | 14.36% | 14.18% | 13.12% | 12.14% | 13.40% | 13.65% | 11.88% |
| Ratio of net investment income (loss) to average net assets – annualized | 8.49% | 6.61% | 6.40% | 6.11% | 6.74% | 6.41% | 6.13% | 6.90% | 5.55% | 6.37% |
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- Definition Antidilutive (Dilutive) Securities Excluded From Computation of Net Income, Per Outstanding Unit, Amount No definition available.
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- Definition Average Net Assets No definition available.
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- Definition Effect Of Equity Capital Activity No definition available.
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- Definition Investment Company, Capital Share Transactions, Per Share No definition available.
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- Definition Investment Company, Discounts, Commissions, And Offering Costs, Per Share No definition available.
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- Definition Investment Company, Distribution to Shareholders from Net Investment Income, Per Share No definition available.
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- Definition Investment Company, Distribution To Shareholders From Realized Gains, Per Share No definition available.
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- Definition Investment Company, Distribution To Shareholders From Return Of Capital, Per Share No definition available.
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- Definition Investment Company, Gain (Loss) On Other, Per Share No definition available.
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- Definition Investment Company, Net Asset Value Per Share, Other Increase (Decrease), Net No definition available.
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- Definition Senior Securities Data No definition available.
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- Definition Statement of Assets and Liabilities Data No definition available.
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- Definition Amount of net assets (liabilities). Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Per share or unit amount of distribution to shareholders. Includes, but is not limited to, dividend and capital gain. Excludes distribution for tax return of capital. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage of expense, after incentive allocation, to average net assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage, before incentive allocation, of expense to average net assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- References No definition available.
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- Definition Per share or unit amount of realized and unrealized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Per share or unit amount of investment income (loss) and realized and unrealized gain (loss) on investment. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Per share or unit amount, after investment expense, of dividend and interest investment income (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Percentage, after incentive allocation, of investment income (loss) to average net assets. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage, before incentive allocation, of investment income (loss) to average net assets. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Per share amount of share issuance by investment company. Includes, but is not limited to, per unit, membership interest, or other ownership interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Market value per share of investment portfolio by investment company. Includes, but is not limited to, per unit, membership interest, or other ownership interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Per share amount of share repurchase by investment company. Includes, but is not limited to, per unit, membership interest, or other ownership interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Percentage increase (decrease) in portfolio market value assuming reinvestment of dividend and capital gain distribution. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount that would be paid, determined under the conditions specified in the contract, if the holder of the share has the right to redeem the shares. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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