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N-2 - USD ($) |  | 3 Months Ended | 12 Months Ended |  |  |  |  |
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Feb. 23, 2022 | Dec. 31, 2024 | Sep. 30, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Sep. 30, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Cover [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Entity Central Index Key |  |  |  |  |  |  |  |  |  | 0001496099 |  |  |  |  |  |  |  |  |
Amendment Flag |  |  |  |  |  |  |  |  |  | false |  |  |  |  |  |  |  |  |
Securities Act File Number |  |  |  |  |  |  |  |  |  | 814-00832 |  |  |  |  |  |  |  |  |
Document Type |  |  |  |  |  |  |  |  |  | 10-K |  |  |  |  |  |  |  |  |
Entity Registrant Name |  |  |  |  |  |  |  |  |  | New Mountain Finance Corporation |  |  |  |  |  |  |  |  |
Entity Address, Address Line One |  |  |  |  |  |  |  |  |  | 1633 Broadway, 48th Floor |  |  |  |  |  |  |  |  |
Entity Address, City or Town |  |  |  |  |  |  |  |  |  | New York |  |  |  |  |  |  |  |  |
Entity Address, State or Province |  |  |  |  |  |  |  |  |  | NY |  |  |  |  |  |  |  |  |
Entity Address, Postal Zip Code |  |  |  |  |  |  |  |  |  | 10019 |  |  |  |  |  |  |  |  |
City Area Code |  |  |  |  |  |  |  |  |  | 212 |  |  |  |  |  |  |  |  |
Local Phone Number |  |  |  |  |  |  |  |  |  | 720-0300 |  |  |  |  |  |  |  |  |
Entity Well-known Seasoned Issuer |  |  |  |  |  |  |  |  |  | Yes |  |  |  |  |  |  |  |  |
Entity Emerging Growth Company |  |  |  |  |  |  |  |  |  | false |  |  |  |  |  |  |  |  |
Fee Table [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shareholder Transaction Expenses [Table Text Block] |  |  |  |  |  |  |  |  |  |
Stockholder transaction expenses: |  |
Sales load (as a percentage of offering price) | N/A | (1)
Offering expenses borne by us (as a percentage of offering price) | N/A | (2)
Dividend reinvestment plan expenses (per sales transaction fee) | $ | 15.00 |  | (3)
Total stockholder transaction expenses (as a percentage of offering price) | — | % |
Annual expenses (as a percentage of net assets attributable to common stock) |  |
Base management fees | 3.36 | % | (4)
Incentive fees payable under the Investment Management Agreement | 2.69 | % | (5)
Interest payments on borrowed funds | 8.41 | % | (6)
Other expenses | 0.81 | % | (7)
Acquired fund fees and expenses | 3.66 | % | (8)
Total annual expenses | 18.93 | % | (9)
Base management fee waiver | (0.28) | % | (10)
Total annual expenses after the base management fee waiver | 18.65 | % | (9)(10)
(1)If applicable, the prospectus or prospectus supplement relating to an offering of our common stock will disclose the applicable sales load. (2)The prospectus supplement corresponding to each offering will disclose the applicable estimated amount of offering expenses of the offering and the offering expenses borne by us as a percentage of the offering price. (3)If a participant elects by written notice to the plan administrator to have the plan administrator sell part or all of the shares held by the plan administrator in the participant's account and remit the proceeds to the participant, the plan administrator is authorized to deduct a $15.00 transaction fee plus a $0.10 per share brokerage commission from the proceeds. The expenses of the dividend reinvestment plan are included in "other expenses." The plan administrator's fees will be paid by us. There will be no brokerage charges or other charges to stockholders who participate in the plan. See Item 8—Financial Statements and Supplementary Data—Note 2. Summary of Significant Accounting Policies in this Annual Report on Form 10-K for additional details regarding our dividend reinvestment plan. (4)The base management fee as of November 1, 2021 pursuant to Amendment No. 1 to the Investment Management Agreement is based on an annual rate of 1.4% of our average gross assets for the two most recent quarters, which equals our total assets on the Consolidated Statements of Assets and Liabilities less cash and cash equivalents. To the extent the Company invests in derivatives, we use the actual value of the derivatives, as reported on our Consolidated Statements of Assets and Liabilities, for purposes of calculating our base management fee. The base management fee reflected in the table above is based on the year ended December 31, 2024 and is calculated without deducting any management fees waived. (5)Assumes that annual incentive fees earned by the Investment Adviser remain consistent with the gross incentive fees earned by the Investment Adviser during the year ended December 31, 2024 and calculated without deducting any incentive fees waived. As of December 31, 2024, we did not have a capital gains incentive fee accrual. As we cannot predict whether we will meet the thresholds for incentive fees under the Investment Management Agreement, the incentive fees paid in subsequent periods, if any, may be substantially different than the fees incurred during the year ended December 31, 2024. For more detailed information about the incentive fee calculations, see Item 1 — Business — Investment Management Agreement in this Annual Report on Form 10-K. (6)We may borrow funds from time to time to make investments to the extent we determine that additional capital would allow us to take advantage of additional investment opportunities or if the economic situation is otherwise conducive to doing so. The costs associated with these borrowings are indirectly borne by our stockholders. The following table summarizes our indebtedness as of December 31, 2024 and the assumed interest rate for each credit facility. See Item 7 — Management's Discussion and Analysis of Financial Condition and Results of Operations — Borrowings in this Annual Report on Form 10-K.
Borrowing |  | Total Outstanding (in millions) |  | Assumed Interest Rate
Unsecured Notes |  | $ | 990.0 |  |  | 6.6%
SBA-guaranteed debentures |  | 300.0 |  | 2.7%
Holdings Credit Facility |  | 294.4 |  | 6.5%
2022 Convertible Notes |  | 260.0 |  | 7.5%
NMFC Credit Facility(1) |  | 27.9 |  | 5.6%
(1)As of December 31, 2024, we had borrowings denominated in Euro ("EUR") of €16.5 million and in British Pound Sterling ("GBP") of £8.7 million that have been converted to United States dollars. (7)"Other expenses" include our overhead expenses, including payments by us under the Administration Agreement based on the allocable portion of overhead and other expenses incurred by the Administrator in performing its obligations to us under the Administration Agreement. Pursuant to the Administration Agreement, the Administrator may, in its own discretion, submit to us for reimbursement some or all of the expenses that the Administrator has incurred on our behalf during any quarterly period. As a result, the amount of expenses for which we will have to reimburse the Administrator may fluctuate in future quarterly periods and there can be no assurance given as to when, or if, the Administrator may determine to limit the expenses that the Administrator submits to us for reimbursement in the future. However, it is expected that the Administrator will continue to support part of our expense burden in the near future and may decide to not calculate and charge through certain overhead related amounts as well as continue to cover some of the indirect costs. The Administrator cannot recoup any expenses that the Administrator has previously waived. This expense ratio is calculated without deducting any expenses waived or reimbursed by the Administrator. For the year ended December 31, 2024, the indirect administrative expenses that our Administrator did not waive of approximately $2.4 million represented approximately 0.07% of our gross assets. See Item 8 — Financial Statements and Supplementary Data — Note 5. Agreements in this Annual Report on Form 10-K. (8)The holders of shares of our common stock indirectly bear the expenses of our investment in NMFC Senior Loan Program III ("SLP III") and NMFC Senior Loan Program IV ("SLP IV"). As SLP III and SLP IV are structured as private joint ventures, no management fees are paid by SLP III and SLP IV. Future expenses for SLP III and SLP IV may be substantially higher or lower because certain expenses may fluctuate over time. (9)The holders of shares of our common stock indirectly bear the cost associated with our annual expenses. (10)The Company entered into a fee waiver agreement, dated March 31, 2021, as subsequently amended on November 2, 2021 and August 3, 2023, pursuant to which, effective as of and for the quarter ended March 31, 2021 through the quarter ended December 31, 2024, the Investment Adviser waived base management fees in order to reach a target base management fee of 1.25% on gross assets. The Investment Adviser cannot recoup management fees that the Investment Adviser has previously waived. The base management fee waiver reflected in the table above is based on the base management fees waived during the year ended December 31, 2024. See Item 8 — Financial Statements and Supplementary Data — Note 5. Agreements in this Annual Report on Form 10-K. |  |  |  |  |  |  |  |  |
Dividend Reinvestment and Cash Purchase Fees |  |  |  |  |  |  |  |  |  | $ 15.00 |  |  |  |  |  |  |  |  |
Other Transaction Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Expenses [Table Text Block] |  |  |  |  |  |  |  |  |  |
Stockholder transaction expenses: |  |
Sales load (as a percentage of offering price) | N/A | (1)
Offering expenses borne by us (as a percentage of offering price) | N/A | (2)
Dividend reinvestment plan expenses (per sales transaction fee) | $ | 15.00 |  | (3)
Total stockholder transaction expenses (as a percentage of offering price) | — | % |
Annual expenses (as a percentage of net assets attributable to common stock) |  |
Base management fees | 3.36 | % | (4)
Incentive fees payable under the Investment Management Agreement | 2.69 | % | (5)
Interest payments on borrowed funds | 8.41 | % | (6)
Other expenses | 0.81 | % | (7)
Acquired fund fees and expenses | 3.66 | % | (8)
Total annual expenses | 18.93 | % | (9)
Base management fee waiver | (0.28) | % | (10)
Total annual expenses after the base management fee waiver | 18.65 | % | (9)(10)
(1)If applicable, the prospectus or prospectus supplement relating to an offering of our common stock will disclose the applicable sales load. (2)The prospectus supplement corresponding to each offering will disclose the applicable estimated amount of offering expenses of the offering and the offering expenses borne by us as a percentage of the offering price. (3)If a participant elects by written notice to the plan administrator to have the plan administrator sell part or all of the shares held by the plan administrator in the participant's account and remit the proceeds to the participant, the plan administrator is authorized to deduct a $15.00 transaction fee plus a $0.10 per share brokerage commission from the proceeds. The expenses of the dividend reinvestment plan are included in "other expenses." The plan administrator's fees will be paid by us. There will be no brokerage charges or other charges to stockholders who participate in the plan. See Item 8—Financial Statements and Supplementary Data—Note 2. Summary of Significant Accounting Policies in this Annual Report on Form 10-K for additional details regarding our dividend reinvestment plan. (4)The base management fee as of November 1, 2021 pursuant to Amendment No. 1 to the Investment Management Agreement is based on an annual rate of 1.4% of our average gross assets for the two most recent quarters, which equals our total assets on the Consolidated Statements of Assets and Liabilities less cash and cash equivalents. To the extent the Company invests in derivatives, we use the actual value of the derivatives, as reported on our Consolidated Statements of Assets and Liabilities, for purposes of calculating our base management fee. The base management fee reflected in the table above is based on the year ended December 31, 2024 and is calculated without deducting any management fees waived. (5)Assumes that annual incentive fees earned by the Investment Adviser remain consistent with the gross incentive fees earned by the Investment Adviser during the year ended December 31, 2024 and calculated without deducting any incentive fees waived. As of December 31, 2024, we did not have a capital gains incentive fee accrual. As we cannot predict whether we will meet the thresholds for incentive fees under the Investment Management Agreement, the incentive fees paid in subsequent periods, if any, may be substantially different than the fees incurred during the year ended December 31, 2024. For more detailed information about the incentive fee calculations, see Item 1 — Business — Investment Management Agreement in this Annual Report on Form 10-K. (6)We may borrow funds from time to time to make investments to the extent we determine that additional capital would allow us to take advantage of additional investment opportunities or if the economic situation is otherwise conducive to doing so. The costs associated with these borrowings are indirectly borne by our stockholders. The following table summarizes our indebtedness as of December 31, 2024 and the assumed interest rate for each credit facility. See Item 7 — Management's Discussion and Analysis of Financial Condition and Results of Operations — Borrowings in this Annual Report on Form 10-K.
Borrowing |  | Total Outstanding (in millions) |  | Assumed Interest Rate
Unsecured Notes |  | $ | 990.0 |  |  | 6.6%
SBA-guaranteed debentures |  | 300.0 |  | 2.7%
Holdings Credit Facility |  | 294.4 |  | 6.5%
2022 Convertible Notes |  | 260.0 |  | 7.5%
NMFC Credit Facility(1) |  | 27.9 |  | 5.6%
(1)As of December 31, 2024, we had borrowings denominated in Euro ("EUR") of €16.5 million and in British Pound Sterling ("GBP") of £8.7 million that have been converted to United States dollars. (7)"Other expenses" include our overhead expenses, including payments by us under the Administration Agreement based on the allocable portion of overhead and other expenses incurred by the Administrator in performing its obligations to us under the Administration Agreement. Pursuant to the Administration Agreement, the Administrator may, in its own discretion, submit to us for reimbursement some or all of the expenses that the Administrator has incurred on our behalf during any quarterly period. As a result, the amount of expenses for which we will have to reimburse the Administrator may fluctuate in future quarterly periods and there can be no assurance given as to when, or if, the Administrator may determine to limit the expenses that the Administrator submits to us for reimbursement in the future. However, it is expected that the Administrator will continue to support part of our expense burden in the near future and may decide to not calculate and charge through certain overhead related amounts as well as continue to cover some of the indirect costs. The Administrator cannot recoup any expenses that the Administrator has previously waived. This expense ratio is calculated without deducting any expenses waived or reimbursed by the Administrator. For the year ended December 31, 2024, the indirect administrative expenses that our Administrator did not waive of approximately $2.4 million represented approximately 0.07% of our gross assets. See Item 8 — Financial Statements and Supplementary Data — Note 5. Agreements in this Annual Report on Form 10-K. (8)The holders of shares of our common stock indirectly bear the expenses of our investment in NMFC Senior Loan Program III ("SLP III") and NMFC Senior Loan Program IV ("SLP IV"). As SLP III and SLP IV are structured as private joint ventures, no management fees are paid by SLP III and SLP IV. Future expenses for SLP III and SLP IV may be substantially higher or lower because certain expenses may fluctuate over time. (9)The holders of shares of our common stock indirectly bear the cost associated with our annual expenses. (10)The Company entered into a fee waiver agreement, dated March 31, 2021, as subsequently amended on November 2, 2021 and August 3, 2023, pursuant to which, effective as of and for the quarter ended March 31, 2021 through the quarter ended December 31, 2024, the Investment Adviser waived base management fees in order to reach a target base management fee of 1.25% on gross assets. The Investment Adviser cannot recoup management fees that the Investment Adviser has previously waived. The base management fee waiver reflected in the table above is based on the base management fees waived during the year ended December 31, 2024. See Item 8 — Financial Statements and Supplementary Data — Note 5. Agreements in this Annual Report on Form 10-K. |  |  |  |  |  |  |  |  |
Management Fees [Percent] |  |  |  |  |  |  |  |  |  | 3.36% |  |  |  |  |  |  |  |  |
Interest Expenses on Borrowings [Percent] |  |  |  |  |  |  |  |  |  | 8.41% |  |  |  |  |  |  |  |  |
Incentive Fees [Percent] |  |  |  |  |  |  |  |  |  | 2.69% |  |  |  |  |  |  |  |  |
Acquired Fund Fees and Expenses [Percent] |  |  |  |  |  |  |  |  |  | 3.66% |  |  |  |  |  |  |  |  |
Other Annual Expenses [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Annual Expenses [Percent] |  |  |  |  |  |  |  |  |  | 0.81% |  |  |  |  |  |  |  |  |
Total Annual Expenses [Percent] |  |  |  |  |  |  |  |  |  | 18.93% |  |  |  |  |  |  |  |  |
Waivers and Reimbursements of Fees [Percent] |  |  |  |  |  |  |  |  |  | 0.28% |  |  |  |  |  |  |  |  |
Net Expense over Assets [Percent] |  |  |  |  |  |  |  |  |  | 18.65% |  |  |  |  |  |  |  |  |
Expense Example [Table Text Block] |  |  |  |  |  |  |  |  |  | The following example, required by the SEC, demonstrates the projected dollar amount of total cumulative expenses that would be incurred over various periods with respect to a hypothetical investment in our common stock. In calculating the following expense amounts, we have assumed that our borrowings and annual operating expenses would remain at the levels set forth in the table above. See footnote 6 above for additional information regarding certain assumptions regarding our level of leverage.
| 1 Year |  | 3 Years |  | 5 Years |  | 10 Years
You would pay the following expenses on a $1,000 investment, assuming a 5.0% annual return without realization of any capital gains | $ | 162 |  |  | $ | 431 |  |  | $ | 638 |  |  | $ | 974 |
Expense Example, Year 01 |  |  |  |  |  |  |  |  |  | $ 162 |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 3 |  |  |  |  |  |  |  |  |  | 431 |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 5 |  |  |  |  |  |  |  |  |  | 638 |  |  |  |  |  |  |  |  |
Expense Example, Years 1 to 10 |  |  |  |  |  |  |  |  |  | $ 974 |  |  |  |  |  |  |  |  |
Purpose of Fee Table , Note [Text Block] |  |  |  |  |  |  |  |  |  | The following table is intended to assist you in understanding the costs and expenses that you will bear directly or indirectly. We caution you that some of the percentages indicated in the table below are estimates and may vary. Except where the context suggests otherwise, whenever this Annual Report on Form 10-K contains a reference to fees or expenses paid by "you", "NMFC", or "us" or that "we", "NMFC", or the "Company" will pay fees or expenses, we will pay such fees and expenses out of our net assets and, consequently, you will indirectly bear such fees or expenses as an investor in us. However, you will not be required to deliver any money or otherwise bear personal liability or responsibility for such fees or expenses. |  |  |  |  |  |  |  |  |
Other Transaction Fees, Note [Text Block] |  |  |  |  |  |  |  |  |  | The prospectus supplement corresponding to each offering will disclose the applicable estimated amount of offering expenses of the offering and the offering expenses borne by us as a percentage of the offering price. |  |  |  |  |  |  |  |  |
Other Expenses, Note [Text Block] |  |  |  |  |  |  |  |  |  | "Other expenses" include our overhead expenses, including payments by us under the Administration Agreement based on the allocable portion of overhead and other expenses incurred by the Administrator in performing its obligations to us under the Administration Agreement. Pursuant to the Administration Agreement, the Administrator may, in its own discretion, submit to us for reimbursement some or all of the expenses that the Administrator has incurred on our behalf during any quarterly period. As a result, the amount of expenses for which we will have to reimburse the Administrator may fluctuate in future quarterly periods and there can be no assurance given as to when, or if, the Administrator may determine to limit the expenses that the Administrator submits to us for reimbursement in the future. However, it is expected that the Administrator will continue to support part of our expense burden in the near future and may decide to not calculate and charge through certain overhead related amounts as well as continue to cover some of the indirect costs. The Administrator cannot recoup any expenses that the Administrator has previously waived. This expense ratio is calculated without deducting any expenses waived or reimbursed by the Administrator. For the year ended December 31, 2024, the indirect administrative expenses that our Administrator did not waive of approximately $2.4 million represented approximately 0.07% of our gross assets. See Item 8 — Financial Statements and Supplementary Data — Note 5. Agreements in this Annual Report on Form 10-K. |  |  |  |  |  |  |  |  |
Management Fee not based on Net Assets, Note [Text Block] |  |  |  |  |  |  |  |  |  | The base management fee as of November 1, 2021 pursuant to Amendment No. 1 to the Investment Management Agreement is based on an annual rate of 1.4% of our average gross assets for the two most recent quarters, which equals our total assets on the Consolidated Statements of Assets and Liabilities less cash and cash equivalents. To the extent the Company invests in derivatives, we use the actual value of the derivatives, as reported on our Consolidated Statements of Assets and Liabilities, for purposes of calculating our base management fee. The base management fee reflected in the table above is based on the year ended December 31, 2024 and is calculated without deducting any management fees waived. |  |  |  |  |  |  |  |  |
Acquired Fund Fees and Expenses, Note [Text Block] |  |  |  |  |  |  |  |  |  | The holders of shares of our common stock indirectly bear the expenses of our investment in NMFC Senior Loan Program III ("SLP III") and NMFC Senior Loan Program IV ("SLP IV"). As SLP III and SLP IV are structured as private joint ventures, no management fees are paid by SLP III and SLP IV. Future expenses for SLP III and SLP IV may be substantially higher or lower because certain expenses may fluctuate over time. |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment Objectives and Practices [Text Block] |  |  |  |  |  |  |  |  |  | Investment Objective and Portfolio We are a leading BDC focused on providing direct lending solutions to U.S. upper middle market companies backed by top private equity sponsors. Our investment objective is to generate current income and capital appreciation through the sourcing and origination of senior secured loans and select junior capital positions, to growing businesses in defensive industries that offer attractive risk-adjusted returns. Our differentiated investment approach leverages the deep sector knowledge and operating resources of New Mountain Capital. Senior secured loans may include traditional first lien loans or unitranche loans. We invest a significant portion of our portfolio in unitranche loans, which are loans that combine both senior and subordinated debt, generally in a first lien position. Because unitranche loans combine characteristics of senior and subordinated debt, they have risks similar to the risks associated with secured debt and subordinated debt. Certain unitranche loan investments may include “last-out” positions, which generally heighten the risk of loss. In some cases, our investments may also include equity interests. We primarily invest in senior secured debt of U.S. sponsor-backed, middle market companies. We define middle market companies as those with annual earnings before interest, taxes, depreciation, and amortization ("EBITDA") of $10 million to $200 million. Our focus is on defensive growth businesses that generally exhibit the following characteristics: (i) acyclicality, (ii) sustainable secular growth drivers, (iii) niche market dominance and high barriers to competitive entry, (iv) recurring revenue and strong free cash flow, (v) flexible cost structures and (vi) seasoned management teams. Similar to us, the investment objective of SBIC I and SBIC II is to generate current income and capital appreciation under the investment criteria we use. However, SBIC I’s and SBIC II's investments must be in SBA eligible small businesses. For additional information on SBA regulations, see "SBA Regulation". Our portfolio may be concentrated in a limited number of industries. As of December 31, 2024, our top five industry concentrations were software, healthcare, business services, investment funds (which includes our investments in our joint ventures) and consumer services. Our targeted investments typically have maturities of between five and ten years and generally range in size between $10.0 million and $125.0 million. This investment size may vary proportionately as the size of our capital base changes. At December 31, 2024, our portfolio consisted of 120 portfolio companies and was invested 63.3% in first lien loans, 6.4% in second lien loans, 3.3% in subordinated debt, 0.1% in structured finance obligations and 26.9% in equity and other, as measured at fair value versus 110 portfolio companies invested 55.9% in first lien loans, 14.1% in second lien loans, 3.0% in subordinated debt and 27.0% in equity and other, as measured at fair value at December 31, 2023. The fair value of our investments, as determined in good faith by our board of directors, was approximately $3,091.0 million in 120 portfolio companies at December 31, 2024 and approximately $3,011.3 million in 110 portfolio companies at December 31, 2023. See Item 7 - Management's Discussion and Analysis of Financial Condition and Results of Operations - Portfolio and Investment Activity in this Annual Report on Form 10-K for details. At December 31, 2024 and December 31, 2023, our weighted average yield to maturity at cost ("YTM at Cost") for income producing investments was approximately 11.0% and 10.9%, respectively. This YTM at Cost calculation assumes that all investments, including secured collateralized agreements, not on non-accrual are purchased at cost on the quarter end date and held until their respective maturities with no prepayments or losses and exited at par at maturity. At December 31, 2024 and December 31, 2023, our weighted average yield to maturity at cost for all investments ("YTM at Cost for Investments") was approximately 9.2% and 9.7%, respectively. This YTM at Cost for Investments calculation assumes that all investments, including secured collateralized agreements, are purchased at cost on the quarter end date and held until their respective maturities with no prepayments or losses and exited at par at maturity. YTM at Cost and YTM at Cost for Investments calculations exclude the impact of existing leverage. YTM at Cost and YTM at Cost for Investments use Sterling Overnight Interbank Average Rate ("SONIA"), Secured Overnight Financing Rate ("SOFR") and Euro Interbank Offered Rate ("EURIBOR") curves at each quarter's end date. The actual yield to maturity may be higher or lower due to the future selection of the SONIA, SOFR and EURIBOR contracts by the individual companies in our portfolio or other factors. The following summarizes our ten largest portfolio company investments and the top ten industries in which we were invested as of December 31, 2024, calculated as a percentage of total assets as of December 31, 2024:
Portfolio Company |  | Percent of Total Assets
NMFC Senior Loan Program III LLC |  | 4.9 | %
New Benevis Topco, LLC/New Benevis Holdco, Inc. |  | 4.3 | %
NMFC Senior Loan Program IV LLC |  | 3.5 | %
NM NL Holdings LP/NM GP Holdco LLC |  | 3.3 | %
UniTek Global Services, Inc. |  | 3.3 | %
TVG-Edmentum Holdings, LLC/Edmentum Ultimate Holdings, LLC |  | 2.8 | %
Knockout Intermediate Holdings I Inc./Kaseya Inc. |  | 2.7 | %
Paw Midco, Inc./AAH Topco, LLC |  | 2.5 | %
Dealer Tire Holdings, LLC |  | 2.4 | %
OA Topco, L.P./OA Buyer, Inc. |  | 2.1 | %
Total |  | 31.8 | %
Industry Type |  | Percent of Total Assets
Software |  | 26.1 | %
Healthcare |  | 15.5 | %
Business Services |  | 15.3 | %
Investment Funds (includes investments in joint ventures) |  | 8.5 | %
Consumer Services |  | 5.9 | %
Education |  | 5.8 | %
Financial Services |  | 3.9 | %
Distribution & Logistics |  | 3.7 | %
Net Lease |  | 3.5 | %
Packaging |  | 2.1 | %
Total |  | 90.3 | %
Investment Criteria The Investment Adviser has identified the following investment criteria and guidelines for use in evaluating prospective portfolio companies. However, not all of these criteria and guidelines were, or will be, met in connection with each of our investments. •Defensive growth industries. We seek to invest in industries that can succeed in both robust and weak economic environments but which are also sufficiently large and growing to achieve high valuations providing enterprise value cushion for our targeted debt securities. •High barriers to competitive entry. We target industries and companies that have well defined industries and well established, understandable barriers to competitive entry. •Recurring revenue. Where possible, we focus on companies that have a high degree of predictability in future revenue. •Flexible cost structure. We seek to invest in businesses that have limited fixed costs and therefore modest operating leverage. •Strong free cash flow and high return on assets. We focus on businesses with a demonstrated ability to produce meaningful free cash flow from operations. We typically target companies that are not asset intensive and that have minimal capital expenditure and minimal working capital growth needs. •Sustainable business and niche market dominance. We seek to invest in businesses that exert niche market dominance in their industry and that have a demonstrated history of sustaining market leadership over time. •Established companies. We seek to invest in established companies with sound historical financial performance. We do not intend to invest in start-up companies or companies with speculative business plans. •Private equity sponsorship. We generally seek to invest in companies in conjunction with private equity sponsors who we know and trust and who have proven capabilities in building value. •Seasoned management team. We generally require that portfolio companies have a seasoned management team with strong corporate governance. Oftentimes we have a historical relationship with or direct knowledge of key managers from previous investment experience. Investment Selection and Process The Investment Adviser believes it has developed a proven, consistent and replicable investment process to execute our investment strategy. The Investment Adviser seeks to identify the most attractive investment sectors from the top down and then works to become the most advantaged investor in these sectors. The steps in the Investment Adviser's process include: •Identifying attractive investment sectors from the top down; •Creating competitive advantages in the selected industry sectors; and •Targeting companies with leading market share and attractive business models in its chosen sectors. Investment Committee The Investment Adviser is managed by a six member Investment Committee, which is responsible for approving purchases and sales of our investments above $10.0 million in aggregate by issuer. The Investment Committee currently consists of Steven B. Klinsky, Robert A. Hamwee, John R. Kline, Adam B. Weinstein and Laura C. Holson. The sixth and final member of the Investment Committee will consist of a New Mountain Capital Managing Director who will hold the position on the Investment Committee on an annual rotating basis. Andre V. Moura served on the Investment Committee from August 2023 to July 2024. Beginning in August 2024, Robert Mulcare was appointed to the Investment Committee for a one year term. In addition, our executive officers and certain investment professionals of the Investment Adviser are invited to all Investment Committee meetings. Purchases and dispositions below $10.0 million may be approved by our Chief Executive Officer. These approval thresholds are subject to change over time. We expect to benefit from the extensive and varied relevant experience of the investment professionals serving on the Investment Committee, which includes expertise in private equity, primary and secondary leveraged credit, private mezzanine finance and distressed debt. The purpose of the Investment Committee is to evaluate and approve, as deemed appropriate, all investments by the Investment Adviser, subject to certain thresholds. The Investment Committee's process is intended to bring the diverse experience and perspectives of the Investment Committee's members to the analysis and consideration of every investment. The Investment Committee also serves to provide investment consistency and adherence to the Investment Adviser's investment philosophies and policies. The Investment Committee also determines appropriate investment sizing and suggests ongoing monitoring requirements. In addition to reviewing investments, the Investment Committee meetings serve as a forum to discuss credit views and outlooks. Potential transactions and investment opportunities are also reviewed on a regular basis. Members of our investment team are encouraged to share information and views on credit with the Investment Committee early in their analysis. This process improves the quality of the analysis and allows the deal team members to work more efficiently. Investment Structure We target debt investments that will yield current income and occasionally provide the opportunity for capital appreciation through equity securities. Our debt investments are typically structured with the maximum seniority and collateral that we can reasonably obtain while seeking to achieve our total return target. Debt Investments The terms of our debt investments are tailored to the facts and circumstances of the transaction and prospective portfolio company and are structured to protect such portfolio company's rights and manage its risk while creating incentives for the portfolio company to achieve its business plan. A substantial source of return is the cash interest that we collect on our debt investments. •First Lien Loans and Bonds. First lien loans and bonds generally have terms of four to seven years, provide for a variable or fixed interest rate, may contain prepayment penalties and are secured by a first priority security interest in all existing and future assets of the borrower. Our first lien loans may also include unitranche loans. We invest a significant portion of our portfolio in unitranche loans, which are loans that combine both senior and subordinated debt, generally in a first-lien position. Because unitranche loans combine characteristics of senior and subordinated debt, they have risks similar to the risks associated with secured debt and subordinated debt. Certain unitranche loan investments may include “last-out” positions, which generally heighten the risk of loss. These first lien loans and bonds may include payment-in-kind ("PIK") interest, which represents contractual interest accrued and added to the principal that generally becomes due at maturity. •Second Lien Loans and Bonds. Second lien loans and bonds generally have terms of five to eight years, provide for a variable or fixed interest rate, may contain prepayment penalties and are secured by a second priority security interest in all existing and future assets of the borrower. These second lien loans and bonds may include PIK interest. •Unsecured Senior, Subordinated and "Mezzanine" Loans and Bonds. Any unsecured investments are generally expected to have terms of five to ten years and provide for a fixed interest rate. Unsecured investments may include PIK interest and may have an equity component, such as warrants to purchase common stock in the portfolio company. In addition, from time to time we may also enter into revolving credit facilities, bridge financing commitments, delayed draw commitments or other commitments which can result in providing future financing to a portfolio company. Equity Investments When we make a debt investment, we may be granted equity in the portfolio company in the same class of security as the sponsor receives upon funding. In addition, we may from time to time make non-control, passive equity co-investments in conjunction with private equity sponsors. We generally seek to structure our passive equity investments, such as direct equity co-investments, to provide us with minority rights provisions and event-driven put rights. We also seek to obtain limited registration rights in connection with these investments, which may include “piggyback” registration rights. Portfolio Company Monitoring We monitor the performance and financial trends of our portfolio companies on at least a quarterly basis. We attempt to identify any developments within the portfolio company, the industry or the macroeconomic environment that may alter any material element of our original investment strategy. Our portfolio monitoring procedures are designed to provide a simple yet comprehensive analysis of our portfolio companies based on their operating performance and underlying business characteristics, which in turn forms the basis of its Risk Rating. See Item 7 - Management's Discussion and Analysis of Financial Condition and Results of Operations -Monitoring of Portfolio Investments in this Annual Report on Form 10-K for details. Exit Strategies/Refinancing We exit our investments typically through one of four scenarios: (i) the sale of the portfolio company itself, resulting in repayment of all outstanding debt, (ii) the recapitalization of the portfolio company in which our loan is replaced with debt or equity from a third party or parties (in some cases, we may choose to participate in the newly issued loan(s)), (iii) the repayment of the initial or remaining principal amount of our loan then outstanding at maturity, or (iv) the sale of the debt investment by us. In some investments, there may be scheduled amortization of some portion of our loan which would result in a partial exit of our investment prior to the maturity of the loan. Our investment objective is to generate current income and capital appreciation through the sourcing and origination of senior secured loans and select junior capital positions, to growing businesses in defensive industries that offer attractive risk-adjusted returns. Our differentiated investment approach leverages the deep sector knowledge and operating resources of New Mountain Capital. Senior secured loans may include traditional first lien loans or unitranche loans. We invest a significant portion of our portfolio in unitranche loans, which are loans that combine both senior and subordinated debt, generally in a first-lien position. Because unitranche loans combine characteristics of senior and subordinated debt, they have risks similar to the risks associated with secured debt and subordinated debt. Certain unitranche loan investments may include “last-out” positions, which generally heighten the risk of loss. In some cases, our investments may also include equity interests. We primarily invest in senior secured debt of U.S. sponsor-backed, middle market companies. We define middle market companies as those with annual earnings before interest, taxes, depreciation, and amortization ("EBITDA") of $10 million to $200 million. Our focus is on defensive growth businesses that generally exhibit the following characteristics: (i) acyclicality, (ii) sustainable secular growth drivers, (iii) niche market dominance and high barriers to competitive entry, (iv) recurring revenue and strong free cash flow, (v) flexible cost structures and (vi) seasoned management teams. Similar to us, the investment objective of SBIC I and SBIC II is to generate current income and capital appreciation under the investment criteria we use. However, SBIC I and SBIC II investments must be in SBA eligible small businesses. Our portfolio may be concentrated in a limited number of industries. As of December 31, 2024, our top five industry concentrations were software, healthcare, business services, investment funds (which includes our investments in our joint ventures) and consumer services. |  |  |  |  |  |  |  |  |
Effects of Leverage [Text Block] |  |  |  |  |  |  |  |  |  | The following table illustrates the effect of leverage on returns from an investment in our common stock assuming various annual returns, net of interest expense and adjusted for unsettled securities purchased. The calculations in the table below are hypothetical. Actual returns may be higher or lower than those appearing below. The calculation assumes (i) $3,246.7 million in total assets as of December 31, 2024, (ii) a weighted average cost of borrowing s of 6.2%, which assumes the weighted average interest rates as of December 31, 2024 for the Unsecured Notes, the SBA-guaranteed debentures, the Holdings Credit Facility and the NMFC Credit Facility, and the interest rate as of December 31, 2024 for the 2022 Convertible Notes, (iii) $1,860.9 million in debt outstanding and (iv) $1,353.3 million in net assets.
Assumed Return on Our Portfolio (Net of Interest Expense) | (10.0)% |  | (5.0)% |  | 0.0% |  | 5.0% |  | 10.0%
Corresponding Return to Stockholder | (32.7)% |  | (20.7)% |  | (8.7)% |  | 3.3% |  | 15.3%
Annual Interest Rate [Percent] |  |  |  |  |  |  |  |  |  | 6.20% |  |  |  |  |  |  |  |  |
Effects of Leverage [Table Text Block] |  |  |  |  |  |  |  |  |  |
Assumed Return on Our Portfolio (Net of Interest Expense) | (10.0)% |  | (5.0)% |  | 0.0% |  | 5.0% |  | 10.0%
Corresponding Return to Stockholder | (32.7)% |  | (20.7)% |  | (8.7)% |  | 3.3% |  | 15.3%
Return at Minus Ten [Percent] |  |  |  |  |  |  |  |  |  | (32.70%) |  |  |  |  |  |  |  |  |
Return at Minus Five [Percent] |  |  |  |  |  |  |  |  |  | (20.70%) |  |  |  |  |  |  |  |  |
Return at Zero [Percent] |  |  |  |  |  |  |  |  |  | (8.70%) |  |  |  |  |  |  |  |  |
Return at Plus Five [Percent] |  |  |  |  |  |  |  |  |  | 3.30% |  |  |  |  |  |  |  |  |
Return at Plus Ten [Percent] |  |  |  |  |  |  |  |  |  | 15.30% |  |  |  |  |  |  |  |  |
Effects of Leverage, Purpose [Text Block] |  |  |  |  |  |  |  |  |  | The following table illustrates the effect of leverage on returns from an investment in our common stock assuming various annual returns, net of interest expense and adjusted for unsettled securities purchased. The calculations in the table below are hypothetical. Actual returns may be higher or lower than those appearing below. |  |  |  |  |  |  |  |  |
Share Price [Table Text Block] |  |  |  |  |  |  |  |  |  | New Mountain Finance Corporation's ("NMFC", the "Company", "we", "us" or "our") common stock is traded on the NASDAQ Global Select Market ("NASDAQ") under the symbol "NMFC". The following table sets forth the net asset value ("NAV") per share of our common stock, the high and low closing sale price for our common stock, the closing sale price as a percentage of NAV and the quarterly distributions per share for each fiscal quarter for the years ended December 31, 2024 and December 31, 2023.
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Fiscal Year Ended |  | NAV Per Share (1) |  | High |  | Low |  | (Discount) Premium of High Closing Sales Price to NAV (3) |  | (Discount) Premium of Low Closing Sales Price to NAV (3) |  | Declared Distributions Per Share (4)(5)(6)
December 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |
Fourth Quarter |  | $ | 12.55 |  |  | $ | 11.94 |  |  | $ | 10.68 |  |  | (4.85) | % |  | (14.89) | % |  | $ | 0.33 |
Third Quarter |  | $ | 12.62 |  |  | $ | 12.50 |  |  | $ | 11.84 |  |  | (0.97) | % |  | (6.20) | % |  | $ | 0.34 |
Second Quarter |  | $ | 12.74 |  |  | $ | 12.72 |  |  | $ | 12.14 |  |  | (0.16) | % |  | (4.72) | % |  | $ | 0.34 |
First Quarter |  | $ | 12.77 |  |  | $ | 13.05 |  |  | $ | 12.25 |  |  | 2.22 | % |  | (4.05) | % |  | $ | 0.36 |
December 31, 2023 |  |  |  |  |  |  |  |  |  |  |  |
Fourth Quarter |  | $ | 12.87 |  |  | $ | 13.21 |  |  | $ | 12.25 |  |  | 2.64 | % |  | (4.82) | % |  | $ | 0.46 | (7)
Third Quarter |  | $ | 13.06 |  |  | $ | 13.10 |  |  | $ | 12.48 |  |  | 0.31 | % |  | (4.44) | % |  | $ | 0.36 |
Second Quarter |  | $ | 13.14 |  |  | $ | 12.69 |  |  | $ | 11.42 |  |  | (3.42) | % |  | (13.09) | % |  | $ | 0.35 |
First Quarter |  | $ | 13.14 |  |  | $ | 13.11 |  |  | $ | 11.63 |  |  | (0.23) | % |  | (11.49) | % |  | $ | 0.32 |
(1)NAV is determined as of the last date in the relevant quarter and therefore may not reflect the NAV per share on the date of the high and low closing sales prices. The NAVs shown are based on outstanding shares at the end of each period. (2)Closing sales price is determined as the high or low closing sales price noted within the respective quarter, not adjusted for distributions. (3)Calculated as of the respective high or low closing sales price divided by the quarter end NAV. (4)Represents the distributions declared or paid for the specified quarter. (5)Tax characteristics of all distributions paid are reported to stockholders on Form 1099 after the end of the calendar year. (6)Includes regular quarterly distributions of $0.32 per share and supplemental distributions related to prior quarter earnings of $0.01, $0.02, $0.02, $0.04, $0.04, $0.04, and $0.03 for the fourth quarter of 2024, third quarter of 2024, second quarter of 2024, first quarter of 2024, fourth quarter of 2023, third quarter of 2023 and second quarter of 2023, respectively. (7)Includes a special distribution of $0.10 per share. |  |  |  |  |  |  |  |  |
Lowest Price or Bid |  | $ 10.68 | $ 11.84 | $ 12.14 | $ 12.25 | $ 12.25 | $ 12.48 | $ 11.42 | $ 11.63 |  |  |  |  |  |  |  |  |  |
Highest Price or Bid |  | $ 11.94 | $ 12.50 | $ 12.72 | $ 13.05 | $ 13.21 | $ 13.10 | $ 12.69 | $ 13.11 |  |  |  |  |  |  |  |  |  |
Highest Price or Bid, Premium (Discount) to NAV [Percent] |  | (4.85%) | (0.97%) | (0.16%) | 2.22% | 2.64% | 0.31% | (3.42%) | (0.23%) |  |  |  |  |  |  |  |  |  |
Lowest Price or Bid, Premium (Discount) to NAV [Percent] |  | (14.89%) | (6.20%) | (4.72%) | (4.05%) | (4.82%) | (4.44%) | (13.09%) | (11.49%) |  |  |  |  |  |  |  |  |  |
NAV Per Share |  | $ 12.55 | $ 12.62 | $ 12.74 | $ 12.77 | $ 12.87 | $ 13.06 | $ 13.14 | $ 13.14 | $ 12.55 | $ 12.87 | $ 12.62 | $ 13.26 |  | $ 13.02 | $ 13.49 |  |  |
Latest Premium (Discount) to NAV [Percent] | (4.80%) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Capital Markets Disruption And Economic Uncertainty Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We are currentl y operating in a period of capital markets disruption and economic uncertainty Disruptions in the capital markets have increased the spread between the yields realized on risk-free and higher risk securities, resulting in illiquidity in parts of the capital markets. These and future market disruptions and/or illiquidity would be expected to have an adverse effect on our business, financial condition, results of operations and cash flows. Unfavorable economic conditions also would be expected to increase our funding costs, limit our access to the capital markets or result in a decision by lenders not to extend credit to us. These events have limited, and could continue to limit, our investment originations and/or our ability to grow, and they could have a material negative impact on our operating results and the fair values of our debt and equity investments. Further, current market conditions may make it difficult for us to obtain debt capital on favorable terms and any failure to do so could have a material adverse effect on our business. The debt capital that will be available to us in the future, if at all, may be at a higher cost and on less favorable terms and conditions than what we would otherwise expect, including being at a higher cost in rising rate environments. If we are unable to raise debt, then our equity investors may not benefit from the potential for increased returns on equity resulting from leverage and we may be limited in our ability to make or fund commitments to portfolio companies. An inability to obtain indebtedness could have a material adverse effect on our business, financial condition or results of operations. |  |  |  |  |  |  |  |  |
Credit Markets Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Adverse developments in the credit markets may impair our ability to secure debt financing. In past economic downturns, such as the financial crisis in the United States that began in mid-2007 and during other times of extreme market volatility, many commercial banks and other financial institutions stopped lending or significantly curtailed their lending activity. In addition, in an effort to stem losses and reduce their exposure to segments of the economy deemed to be high risk, some financial institutions limited routine refinancing and loan modification transactions and even reviewed the terms of existing facilities to identify bases for accelerating the maturity of existing lending facilities. If these conditions recur, for example as a result of continued elevated interest rates or global conflict, it may be difficult for us to obtain desired financing to finance the growth of our investments on acceptable economic terms, or at all. If we are unable to consummate credit facilities on commercially reasonable terms, our liquidity may be reduced significantly. If we are unable to repay amounts outstanding under our credit facilities or any facility we may enter into and are declared in default or are unable to renew or refinance any such facility, it would limit our ability to initiate significant originations or to operate our business in the normal course. These situations may arise due to circumstances that we may be unable to control, such as inaccessibility of the credit markets, a severe decline in the value of the U.S. dollar, a further economic downturn or an operational problem that affects third parties or us, and could materially damage our business. Moreover, we are unable to predict when economic and market conditions may become more favorable. Even if such conditions improve broadly and significantly over the long term, adverse conditions in particular sectors of the financial markets could adversely impact our business. |  |  |  |  |  |  |  |  |
Global Economic Political And Market Conditions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Further downgrades of the U.S. credit rating, impending automatic spending cuts or another government shutdown could negatively impact our liquidity, financial condition and earnings. The U.S. debt ceiling and budget deficit concerns have increased the possibility of additional credit-rating downgrades and economic slowdowns, or a recession in the United States. U.S. lawmakers have passed legislation to raise the federal debt ceiling on multiple occasions. On January 2, 2025, U.S. lawmakers reinstated the debt ceiling to the level of obligations accrued during the suspension or $36.1 trillion. As of January 22, 2025, the US government has hit the debt ceiling and exceeded its borrowing limit. Despite taking action to suspend the debt ceiling, ratings agencies have threatened to lower the long-term sovereign credit rating on the United States, including Fitch downgrading the U.S. government’s long-term rating from AAA to AA+ in August 2023 and Moody’s lowering the U.S. government’s credit rating outlook from “stable” to “negative” in November 2023. Although, in August 2024, Moody’s affirmed the U.S. government’s credit rating at AA+, with a stable outlook, there is no guarantee that there will not be a further downgrade in the future. The impact of any further downgrades to the U.S. government’s sovereign credit rating or its perceived creditworthiness could adversely affect the U.S. and global financial markets and economic conditions. These developments could cause interest rates and borrowing costs to rise, which may negatively impact our ability to access the debt markets on favorable terms. In addition, disagreement over the federal budget has caused the U.S. federal government to shut down for periods of time, and may lead to additional shutdowns in the future. Continued adverse political and economic conditions could have a material adverse effect on our business, financial condition and results of operations. |  |  |  |  |  |  |  |  |
Worldwide Economic, Political, Regulatory And Financial Market RIsk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | U.S. and worldwide economic, political, regulatory and financial market conditions may adversely affect our business, results of operations and financial condition, including our revenue growth and profitability. We and our portfolio companies are subject to regulation by laws at the U.S. federal, state and local levels. These laws and regulations, as well as their interpretation, could change from time to time, including as the result of interpretive guidance or other directives from the U.S. President and others in the executive branch, and new laws, regulations and interpretations could also come into effect. Any such new or changed laws or regulations could have a material adverse effect on our business, and political uncertainty could increase regulatory uncertainty in the near term. The effects of legislative and regulatory proposals directed at the financial services industry or affecting taxation, could negatively impact the operations, cash flows or financial condition of us and our portfolio companies, impose additional costs on us or our portfolio companies, intensify the regulatory supervision of us or our portfolio companies or otherwise adversely affect our business or the business of our portfolio companies. In addition, if we do not comply with applicable laws and regulations, we could lose any licenses that we then hold for the conduct of business and could be subject to civil fines and criminal penalties. Over the last several years, there also has been an increase in regulatory attention to the extension of credit outside of the traditional banking sector, raising the possibility that some portion of the non-bank financial sector will be subject to new regulation. While it cannot be known at this time whether any regulation will be implemented or what form it will take, increased regulation of non-bank credit extension could negatively impact our operations, cash flows or financial condition, impose additional costs on us, intensify the regulatory supervision of us or otherwise adversely affect our business, financial condition and results of operations. Although we cannot predict the impact, if any, of these changes to our business, they could adversely affect our business, financial condition, operating results and cash flows. Until we know what policy changes are made and how those changes impact business and the business of our competitors over the long term, we will not know if, overall, it will benefit from them or be negatively affected by them. In 2010, a financial crisis emerged in Europe, triggered by high budget deficits and rising direct and contingent sovereign debt, which created concerns about the ability of certain nations to continue to service their sovereign debt obligations. Risks resulting from such debt crisis, including any austerity measures taken in exchange for bailout of certain nations, and any future debt crisis in Europe or any similar crisis elsewhere could have a detrimental impact on the global economic recovery, sovereign and non-sovereign debt in certain countries and the financial condition of financial institutions generally. On January 31, 2020, the United Kingdom (the “UK”) ended its membership in the European Union (“Brexit”). Under the terms of the withdrawal agreement negotiated and agreed between the UK and the European Union, the UK’s departure from the European Union was followed by a transition period (the “Transition Period”), which ran until December 31, 2020 and during which the UK continued to apply European Union law and was treated for all material purposes as if it were still a member of the European Union. On December 24, 2020, the European Union and UK governments signed a trade deal that became provisionally effective on January 1, 2021 and that now governs the relationship between the UK and European Union (the “Trade Agreement”). The Trade Agreement implements significant regulation around trade, transport of goods and travel restrictions between the UK and the European Union. Notwithstanding the foregoing, the longer term economic, legal, political and social implications of Brexit are unclear at this stage and are likely to continue to lead to ongoing political and economic uncertainty and periods of increased volatility in both the UK and in wider European markets for some time. In particular, Brexit could lead to calls for similar referendums in other European jurisdictions, which could cause increased economic volatility in the European and global markets. This mid- to long-term uncertainty could have adverse effects on the economy generally and on our ability to earn attractive returns. In particular, currency volatility could mean that our returns are adversely affected by market movements and could make it more difficult, or more expensive, for us to execute prudent currency hedging policies. Potential decline in the value of the British Pound and/or the Euro against other currencies, along with the potential further downgrading of the UK’s sovereign credit rating, could also have an impact on the performance of certain investments made in the UK or Europe. |  |  |  |  |  |  |  |  |
Geopolitical Unrest, Terrorist Attacks, Or Acts Of War Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Increased geopolitical unrest, terrorist attacks, or acts of war may affect any market for our common stock, impact the businesses in which we invest, and harm our business, operating results, and financial conditions. The continued threat of global terrorism and the impact of military and other action will likely continue to cause volatility in the economies of certain countries and various aspects thereof, including in prices of commodities, and could affect our financial results. Our portfolio investments may involve significant strategic assets having a national or regional profile. The nature of these assets could expose them to a greater risk of being the subject of a terrorist attack than other assets or businesses. Any terrorist attacks that occur at or near such assets would likely cause significant harm to employees, property and, potentially, the surrounding community, and may result in losses far in excess of available insurance coverage. As a result of global events and continued terrorism concerns, insurers significantly reduced the amount of insurance coverage available for liability to persons other than employees for claims resulting from acts of terrorism, war or similar events. As a result of a terrorist attack or terrorist activities in general, we may not be able to obtain insurance coverage and other endorsements at commercially reasonable prices or at all. In addition, various social and political circumstances in the United States and around the world (including wars and other forms of conflict, terrorist acts, security operations and catastrophic events such as fires, floods, earthquakes, tornadoes, hurricanes and global health epidemics), may also contribute to increased market volatility and economic uncertainties. Such events, including rising trade tensions between the United States and China; other uncertainties regarding actual and potential shifts in U.S. and foreign, trade, economic and other policies with other countries; the ongoing conflict between Russia and Ukraine; and ongoing conflict in the Middle East. In response to the conflict between Russia and Ukraine, the United States and other countries have imposed sanctions or other restrictive actions against Russia. Any of the above factors, including sanctions, export controls, tariffs, trade wars and other governmental actions, could have a material adverse effect on our business, financial condition, cash flows and results of operations and could cause the market value of our common stock to decline. |  |  |  |  |  |  |  |  |
Inflation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Inflation and rising commodity prices may adversely impact our portfolio companies. Inflation may affect our investments adversely in a number of ways. During periods of rising inflation, interest and distribution rates of any instrument we or entities related to portfolio investments may have issued could increase. Inflationary expectations or periods of rising inflation could also be accompanied by the rising prices of commodities which are critical to the operation of portfolio companies. Portfolio companies may have fixed income streams and, therefore, be unable to pay the interest amounts and other payments on our portfolio investments. The market value of such investments may decline in value in times of higher inflation rates. Some of our portfolio investments may have income linked to inflation through contractual rights or other means. However, as inflation may affect both income and expenses, any increase in income may not be sufficient to cover increases in expenses. |  |  |  |  |  |  |  |  |
Legal, Regulatory And Policy Uncertainty In Government Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | There is uncertainty surrounding potential legal, regulatory and policy changes by new presidential administrations in the United States that may directly affect financial institutions and the global economy. Following the November 2024 elections in the United States, the Republican Party controls the Presidency, the Senate and the House of Representatives. Despite political tensions and uncertainty, changes in federal policy, including tax policies, and positions of regulatory agencies are expected to occur over time through policy and personnel changes, which may lead to changes involving the level of oversight and focus on the financial services industry or the tax rates paid by corporate entities. The nature, timing and economic and political effects of potential changes to the current legal and regulatory framework affecting financial institutions remain highly uncertain. In addition, in June 2024, the U.S. Supreme Court in Loper Bright Enterprises v. Raimondo reversed its longstanding approach under the Chevron doctrine, which provided for judicial deference to regulatory agencies. As a result of this decision, we cannot be sure whether there will be increased challenges to existing agency regulations or how lower courts will apply the Loper decision in the context of other regulatory schemes without more specific guidance from the U.S. Supreme Court. For example, the U.S. Supreme Court's decision in Loper could significantly impact how federal agencies will regulate consumer protection, advertising, cybersecurity, privacy, anti-corruption and anti-money laundering practices and other regulatory regimes with which we are required to comply. Any such regulatory developments could result in uncertainty about and changes in the ways such regulations apply to us, and may require additional resources to ensure our continued compliance. Uncertainty surrounding future changes may adversely affect our operating environment and therefore our business, financial condition, results of operations and growth prospects. Our business is dependent on bank relationships and recent strain on the banking system may adversely impact us. The financial markets have previously encountered volatility associated with concerns about the balance sheets of banks, especially small and regional banks that may have significant losses associated with investments that make it difficult to fund demands to withdraw deposits and other liquidity needs. Although the federal government has announced measures to assist these banks and protect depositors in the past, there is no guarantee that the federal government will do so again in the future and other banks may be materially and adversely impacted. Our business is dependent on bank relationships. Continued strain on the financial health of banks with which we (or our portfolio companies) do or may in the future do business may adversely impact our business, financial condition and results of operations. |  |  |  |  |  |  |  |  |
Changes To U.S. Tariff And Trade Policies [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Changes to U.S. tariff and trade policies may have a negative impact on our portfolio companies, which may in turn negatively impact us. Potential significant changes in U.S. trade policies and potential tariffs may create uncertainty regarding the relationship between the United States and certain other countries with respect to trade policies, treaties and tariffs. These developments, or the perception that any of them could occur, may have a material adverse effect on global economic conditions and the stability of global financial markets, and may significantly reduce global trade and, in particular, trade between the impacted nations and the United States. These factors could restrict our portfolio companies' access to suppliers or customers or increase the cost of such goods, which may have a material adverse effect on their business, financial condition and results of operations, which in turn could negatively impact us. |  |  |  |  |  |  |  |  |
Credit Losses Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may suffer credit losses. Investments in small and middle market businesses are highly speculative and involve a high degree of risk of credit loss. These risks are likely to increase during volatile economic periods, such as the United States and many other economies have recently been experiencing. |  |  |  |  |  |  |  |  |
Tariff And Import And Export Regulations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Changes to U.S. tariff and import/export regulations may have a negative effect on our portfolio companies and, in turn, harm us. There has been on-going discussion and commentary regarding potential significant changes to U.S. trade policies, treaties and tariffs. The current U.S. presidential administration, along with Congress, have created significant uncertainty about the future relationship between the United States and other countries with respect to the trade policies, treaties and tariffs. These developments, or the perception that any of them could occur, may have a material adverse effect on global economic conditions and the stability of global financial markets, and may significantly reduce global trade and, in particular, trade between the impacted nations and the United States. Any of these factors could depress economic activity and restrict our portfolio companies' access to suppliers or customers and have a material adverse effect on their business, financial condition and results of operations, which in turn would negatively impact us. |  |  |  |  |  |  |  |  |
Portfolio Value Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | There is uncertainty as to the value of our portfolio investments because most of our investments are, and may continue to be in private companies and recorded at fair value. In addition, the fair values of our investments are determined by our board of directors in accordance with our valuation policy. Some of our investments are and may be in the form of securities or loans that are not publicly traded, and these investments may not have a readily available market quotation. Under the 1940 Act, we are required to carry our portfolio investments at market value or, if there is no readily available market quotation, at fair value as determined in good faith by our board of directors, including reflection of significant events affecting the value of our securities. We value our investments for which we do not have readily available market quotations quarterly, or more frequently as circumstances require, at fair value as determined in good faith by our board of directors in accordance with our valuation policy, which is at all times consistent with GAAP and the 1940 Act. Our board of directors utilizes the services of one or more independent third-party valuation firms to aid it in determining the fair value with respect to our material unquoted assets in accordance with our valuation policy. The inputs into the determination of fair value of these investments may require significant management judgment or estimation. Even if observable market data is available, such information may be the result of consensus pricing information or broker quotes, which include a disclaimer that the broker would not be held to such a price in an actual transaction. The non-binding nature of consensus pricing and/or quotes accompanied by disclaimers materially reduces the reliability of such information. The types of factors that the board of directors takes into account in determining the fair value of our investments generally include, as appropriate: available market data, including relevant and applicable market trading and transaction comparables, applicable market yields and multiples, security covenants, call protection provisions, information rights, the nature and realizable value of any collateral, the portfolio company's ability to make payments, its earnings and discounted cash flows and the markets in which it does business, comparisons of financial ratios of peer companies that are public, comparable merger and acquisition transactions and the principal market and enterprise values. Since these valuations, and particularly valuations of private securities and private companies, are inherently uncertain, may fluctuate over short periods of time and may be based on estimates, our determinations of fair value may differ materially from the values that would have been used if a ready market for these securities existed. Due to this uncertainty, our fair value determinations may cause our net asset value, on any given date, to be materially understated or overstated. In addition, investors purchasing our common stock based on an overstated net asset value would pay a higher price than the realizable value that our investments might warrant. We may adjust quarterly the valuation of our portfolio to reflect our board of directors' determination of the fair value of each investment in our portfolio. Any changes in fair value are recorded in our statement of operations as net change in unrealized appreciation or depreciation. |  |  |  |  |  |  |  |  |
Investment Objectives Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our ability to achieve our investment objective depends on key investment personnel of the Investment Adviser. If the Investment Adviser were to lose any of its key investment personnel, our ability to achieve our investment objective could be significantly harmed. We depend on the investment judgment, skill and relationships of the investment professionals of the Investment Adviser, particularly Steven B. Klinsky, Robert A. Hamwee, John R. Kline and Laura C. Holson, as well as other key personnel to identify, evaluate, negotiate, structure, execute, monitor and service our investments. The Investment Adviser, as an affiliate of New Mountain Capital, is supported by New Mountain Capital's team, which as of December 31, 2024 consisted of approximately 270 employees and senior advisors of New Mountain Capital and its affiliates to fulfill its obligations to us under the Investment Management Agreement. The Investment Adviser may also depend upon New Mountain Capital to obtain access to investment opportunities originated by the professionals of New Mountain Capital and its affiliates. Our future success depends to a significant extent on the continued service and coordination of the key investment personnel of the Investment Adviser. The departure of any of these individuals could have a material adverse effect on our ability to achieve our investment objective. The Investment Committee, which oversees our investment activities, is provided by the Investment Adviser. The Investment Committee currently consists of six members. The loss of any member of the Investment Committee or of other senior professionals of the Investment Adviser and its affiliates without suitable replacement could limit our ability to achieve our investment objective and operate as we anticipate. This could have a material adverse effect on our financial condition, results of operations and cash flows. To achieve our investment objective, the Investment Adviser may hire, train, supervise and manage new investment professionals to participate in its investment selection and monitoring process. If the Investment Adviser is unable to find investment professionals or do so in a timely manner, our business, financial condition and results of operations could be adversely affected. |  |  |  |  |  |  |  |  |
Constraint On Operations By Regulation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The 1940 Act and the Code impose numerous constraints on the operations of BDCs and RICs, which could adversely affect our business. The 1940 Act and the Code impose numerous constraints on the operations of BDCs and RICs that do not apply to the other investment vehicles previously managed by the investment professionals of the Investment Adviser. For example, under the 1940 Act, BDCs are required to invest at least 70.0% of their total assets primarily in "qualifying" assets such as U.S. private or thinly traded companies, cash, cash equivalents, U.S. government securities and other high quality debt investments that mature in one year or less. Moreover, qualification for taxation as a RIC under Subchapter M of the Code requires satisfaction of source-of-income, asset diversification and annual distribution requirements. The failure to comply with these provisions in a timely manner could prevent us from qualifying as a BDC or as a RIC and could force us to pay unexpected taxes and penalties, which would have a material adverse effect on our performance. If we fail to maintain our status as a BDC or tax treatment as a RIC, our operating flexibility could be significantly reduced. |  |  |  |  |  |  |  |  |
Competitive Market Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We operate in a highly competitive market for investment opportunities and may not be able to compete effectively. We compete for investments with other BDCs and investment funds (including private equity and hedge funds), as well as traditional financial services companies such as commercial banks and other sources of funding. Many of our competitors are substantially larger and have considerably greater financial, technical and marketing resources than we do. For example, some competitors may have a lower cost of capital and access to funding sources that are not available to us. In addition, some of our competitors may have higher risk tolerances or different risk assessments than us. Furthermore, many of our competitors have greater experience operating under, or are not subject to, the regulatory restrictions that the 1940 Act imposes on us as a BDC or the source-of-income, asset diversification and distribution requirements that we must satisfy to maintain our tax treatment as a RIC. These characteristics could allow our competitors to consider a wider variety of investments, establish more relationships and offer better pricing and more flexible structuring than we are able to do. We may lose investment opportunities if our pricing, terms and structure do not match those of our competitors. With respect to the investments that we make, we do not seek to compete based primarily on the interest rates we may offer, and we believe that some of our competitors may make loans with interest rates that may be lower than the rates we offer. In the secondary market for acquiring existing loans, we expect to compete generally on the basis of pricing terms. If we match our competitors' pricing, terms and structure, we may experience decreased net interest income, lower yields and increased risk of credit loss. If we are forced to match our competitors' pricing, terms and structure, we may not be able to achieve acceptable returns on our investments or may bear substantial risk of capital loss. Part of our competitive advantage stems from the fact that we believe the market for middle market lending is underserved by traditional bank lenders and other financial sources. A significant increase in the number and/or the size of our competitors in this target market could force us to accept less attractive investment terms. We may also compete for investment opportunities with accounts managed by the Investment Adviser or its affiliates. Although the Investment Adviser allocates opportunities in accordance with its policies and procedures, allocations to such other accounts reduces the amount and frequency of opportunities available to us and may not be in our best interests and, consequently, our stockholders. Moreover, the performance of investment opportunities is not known at the time of allocation. If we are not able to compete effectively, our business, financial condition and results of operations may be adversely affected, thus affecting our business, financial condition and results of operations. Because of this competition, there can be no assurance that we will be able to identify and take advantage of attractive investment opportunities that we identify or that we will be able to fully invest our available capital. |  |  |  |  |  |  |  |  |
Future Growth Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our business, results of operations and financial condition depend on our ability to manage future growth effectively. Our ability to achieve our investment objective and to grow depends on the Investment Adviser's ability to identify, invest in and monitor companies that meet our investment criteria. Accomplishing this result on a cost-effective basis is largely a function of the Investment Adviser's structuring of the investment process, its ability to provide competent, attentive and efficient services to us and its ability to access financing on acceptable terms. The Investment Adviser has substantial responsibilities under the Investment Management Agreement and may also be called upon to provide managerial assistance to our eligible portfolio companies. These demands on the time of the Investment Adviser and its investment professionals may distract them or slow our rate of investment. In order to grow, we and the Investment Adviser may need to retain, train, supervise and manage new investment professionals. However, these investment professionals may not be able to contribute effectively to the work of the Investment Adviser. If we are unable to manage our future growth effectively, our business, results of operations and financial condition could be materially adversely affected. |  |  |  |  |  |  |  |  |
Management Fee And Incentive Fee Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The management fee and incentive fee may induce the Investment Adviser to make speculative investments. The incentive fee payable to the Investment Adviser may create an incentive for the Investment Adviser to pursue investments that are risky or more speculative than would be the case in the absence of such compensation arrangement, which could result in higher investment losses, particularly during cyclical economic downturns. The incentive fee payable to the Investment Adviser is calculated based on a percentage of our return on investment capital. This may encourage the Investment Adviser to use leverage to increase the return on our investments. In addition, because the base management fee is payable based upon our gross assets, which includes any borrowings for investment purposes, but excludes cash and cash equivalents for investment purposes, the Investment Adviser may be further encouraged to use leverage to make additional investments. Under certain circumstances, the use of leverage may increase the likelihood of default, which would impair the value of our common stock. The incentive fee payable to the Investment Adviser also may create an incentive for the Investment Adviser to invest in instruments that have a deferred interest feature, even if such deferred payments would not provide the cash necessary to pay current distributions to our stockholders. Under these investments, we would accrue the interest over the life of the investment but would not receive the cash income from the investment until the end of the investment's term, if at all. Our net investment income used to calculate the income portion of the incentive fee, however, includes accrued interest. Thus, a portion of the incentive fee would be based on income that we have not yet received in cash and may never receive in cash if the portfolio company is unable to satisfy such interest payment obligations. In addition, the "catch-up" portion of the incentive fee may encourage the Investment Adviser to accelerate or defer interest payable by portfolio companies from one calendar quarter to another, potentially resulting in fluctuations in timing and dividend amounts. |  |  |  |  |  |  |  |  |
Investment Advisor Incentive Compensation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may be obligated to pay the Investment Adviser incentive compensation even if we incur a loss. The Investment Adviser is entitled to incentive compensation for each fiscal quarter in an amount equal to a percentage of the excess of our Pre-Incentive Fee Net Investment Income for that quarter (before deducting incentive compensation) above a performance threshold for that quarter. Accordingly, since the performance threshold is based on a percentage of our net asset value, decreases in our net asset value make it easier to achieve the performance threshold. Our Pre-Incentive Fee Net Investment Income for incentive compensation purposes excludes realized and unrealized capital losses or depreciation that it may incur in the fiscal quarter, even if such capital losses or depreciation result in a net loss on our statement of operations for that quarter. Thus, we may be required to pay the Investment Adviser incentive compensation for a fiscal quarter even if there is a decline in the value of our portfolio or we incur a net loss for that quarter. |  |  |  |  |  |  |  |  |
Capital Gains Incentive Fee Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The incentive fee we pay to the Investment Adviser with respect to capital gains may be effectively greater than 20.0%. As a result of the operation of the cumulative method of calculating the capital gains portion of the incentive fee we pay to the Investment Adviser, the cumulative aggregate capital gains fee received by the Investment Adviser could be effectively greater than 20.0%, depending on the timing and extent of subsequent net realized capital losses or net unrealized depreciation. We cannot predict whether, or to what extent, this payment calculation would affect your investment in our common stock. |  |  |  |  |  |  |  |  |
Shared Employees Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may face risks due to shared employees between our Investment Adviser and its affiliates and other activities of the personnel of our Investment Adviser. Our Investment Adviser expects to rely heavily on the extensive expertise and industry relationships developed by the employees and certain senior advisors of certain of its affiliates to identify and evaluate potential investment opportunities for us. Research from the Investment Adviser's private equity strategy on our behalf will be used to benefit other strategies and clients of our Investment Adviser, its affiliates and affiliated funds. By reason of their responsibilities in connection with their other activities, certain personnel of our Investment Adviser (or employees and affiliates thereof) may acquire confidential or material non-public information or be restricted from initiating transactions in certain securities. In those instances, we will not be free to act upon any such information. Due to these restrictions, we may not be able to initiate a transaction that we otherwise might have initiated and may not be able to sell a portfolio investment that we otherwise might have sold. Conversely, we may not have access to material non-public information in the possession of our Investment Adviser and its affiliates which might be relevant to an investment decision to be made by us, and we may initiate a transaction or sell a portfolio investment which, if such information had been known to us, may not have been undertaken. See also "—The Investment Committee, the Investment Adviser or its affiliates may, from time to time, possess material non-public information, limiting our investment discretion." |  |  |  |  |  |  |  |  |
Additional Consulting Fees Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may pay additional consulting fees to New Mountain Capital’s Executive Advisory Council. The Investment Adviser may consult New Mountain Capital's Executive Advisory Council from time to time concerning general industry trends, related matters and specific investment diligence. Members of the Executive Advisory Council may be paid by us for project‑related consulting fees and reimbursed by us for their reasonable and documented out‑of‑pocket expenses in connection with specific diligence for a potential portfolio company. |  |  |  |  |  |  |  |  |
Leverage Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We borrow money, which could magnify the potential for gain or loss on amounts invested in us and increase the risk of investing in us. We borrow money as part of our business plan. Borrowings, also known as leverage, magnify the potential for gain or loss on invested equity capital and may, consequently, increase the risk of investing in us. We expect to continue to use leverage to finance our investments, through senior securities issued by banks and other lenders. Lenders of these senior securities have fixed dollar claims on our assets that are superior to claims of our common stockholders and we would expect such lenders to seek recovery against our assets in the event of default. If the value of our assets decreases, leveraging would cause our net asset value to decline more sharply than it otherwise would have had it not leveraged. Similarly, any decrease in our income would cause our net income to decline more sharply than it would have had it not borrowed. Such a decline could adversely affect our ability to make common stock distribution payments. In addition, because our investments may be illiquid, we may be unable to dispose of them or to do so at a favorable price in the event we need to do so if we are unable to refinance any indebtedness upon maturity and, as a result, we may suffer losses. Leverage is generally considered a speculative investment technique and increases the risks associated with investing in our securities. Our ability to service any debt that we incur depends largely on our financial performance and is subject to prevailing economic conditions and competitive pressures. Moreover, as the Investment Adviser's management fee is payable to the Investment Adviser based on gross assets, including those assets acquired through the use of leverage, the Investment Adviser may have a financial incentive to incur leverage which may not be consistent with our interests and the interests of our common stockholders. In addition, holders of our common stock will, indirectly, bear the burden of any increase in our expenses as a result of leverage, including any increase in the management fee payable to the Investment Adviser. The following tables summarizes our indebtedness outstanding at principal value and the weighted average interest rates of each credit facility for the year ended December 31, 2024:
Borrowing |  | Total Outstanding (in millions) |  | Weighted Average Interest Rate
Unsecured Notes |  | $ | 990.0 |  |  | 6.6 | %
SBA-guaranteed debentures |  | 300.0 |  | 2.7 | %
Holdings Credit Facility |  | 294.4 |  | 7.5 | %
2022 Convertible Notes |  | 260.0 |  | 7.5 | %
NMFC Credit Facility |  | 27.9 |  | 7.0 | %
Illustration. The following table illustrates the effect of leverage on returns from an investment in our common stock assuming various annual returns, net of interest expense and adjusted for unsettled securities purchased. The calculations in the table below are hypothetical. Actual returns may be higher or lower than those appearing below. The calculation assumes (i) $3,246.7 million in total assets as of December 31, 2024, (ii) a weighted average cost of borrowing s of 6.2%, which assumes the weighted average interest rates as of December 31, 2024 for the Unsecured Notes, the SBA-guaranteed debentures, the Holdings Credit Facility and the NMFC Credit Facility, and the interest rate as of December 31, 2024 for the 2022 Convertible Notes, (iii) $1,860.9 million in debt outstanding and (iv) $1,353.3 million in net assets.
Assumed Return on Our Portfolio (Net of Interest Expense) | (10.0)% |  | (5.0)% |  | 0.0% |  | 5.0% |  | 10.0%
Corresponding Return to Stockholder | (32.7)% |  | (20.7)% |  | (8.7)% |  | 3.3% |  | 15.3%
Covenent Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we are unable to comply with the covenants or restrictions in our borrowings, our business could be materially adversely affected. The Holdings Credit Facility includes covenants that, subject to exceptions, restrict our ability to pay distributions, create liens on assets, make investments, make acquisitions and engage in mergers or consolidations. The Holdings Credit Facility also includes a change of control provision that accelerates the indebtedness under the facility in the event of certain change of control events. Complying with these restrictions may prevent us from taking actions that we believe would help us grow our business or are otherwise consistent with our investment objective. These restrictions could also limit our ability to plan for or react to market conditions or meet extraordinary capital needs or otherwise restrict corporate activities. In addition, the restrictions contained in the Holdings Credit Facility could limit our ability to make distributions to our stockholders in certain circumstances, which could result in us failing to qualify as a RIC and thus becoming subject to U.S. federal income tax imposed at corporate rates (and any applicable state and local taxes). Certain of our Unsecured Notes are subject to certain covenants, including covenants such as information reporting, maintenance of our status as a BDC under the 1940 Act and a RIC under the Code, minimum stockholders' equity, minimum asset coverage ratio, and prohibitions on certain fundamental changes, as well as customary events of default with customary cure and notice, including, without limitation, nonpayment, misrepresentation in a material respect, breach of covenant, cross-default under our other indebtedness or certain significant subsidiaries, certain judgments and orders, and certain events of bankruptcy. In addition, we are obligated to offer to prepay the Unsecured Notes (excluding the 8.250% Unsecured Notes) at par if the Investment Adviser, or an affiliate thereof, ceases to be our investment adviser or if certain change in control events occur with respect to the Investment Adviser. The 2022 Convertible Notes are subject to certain covenants, including covenants requiring us to provide financial information to the holders of the Convertible Notes and the trustee if we cease to be subject to the reporting requirements of the Exchange Act. These covenants are subject to limitations and exceptions. In addition, if certain corporate events occur, holders of the 2022 Convertible Notes may require us to repurchase for cash all or part of their 2022 Convertible Notes at a repurchase price equal to 100.0% of the principal amount of the 2022 Convertible Notes to be repurchased, plus accrued and unpaid interest through, but excluding, the repurchase date. The NMFC Credit Facility includes customary covenants, including certain financial covenants related to asset coverage and liquidity and other maintenance covenants, as well as customary events of default. The breach of any of the covenants or restrictions, unless cured within the applicable grace period, would result in a default under the applicable credit facility that would permit the lenders thereunder to declare all amounts outstanding to be due and payable. In such an event, we may not have sufficient assets to repay such indebtedness. As a result, any default could have serious consequences to our financial condition. An event of default or an acceleration under the credit facilities could also cause a cross-default or cross-acceleration of another debt instrument or contractual obligation, which would adversely impact our liquidity. We may not be granted waivers or amendments to the credit facilities if for any reason we are unable to comply with it, and we may not be able to refinance the credit facilities on terms acceptable to us, or at all. |  |  |  |  |  |  |  |  |
Credit Facility Terms Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The terms of our credit facilities may contractually limit our ability to incur additional indebtedness. We will need additional capital to fund new investments and grow our portfolio of investments. We intend to access the capital markets periodically to issue debt or equity securities or borrow from financial institutions in order to obtain such additional capital. We believe that having the flexibility to incur additional leverage could augment the returns to our stockholders and would be in the best interests of our stockholders. Even though our board of directors and our stockholders have approved a resolution permitting us to be subject to a 150.0% asset coverage ratio effective as of June 9, 2018, contractual leverage limitations under our existing credit facilities or future borrowings may limit our ability to incur additional indebtedness. Currently, our NMFC Credit Facility restricts our ability to incur additional indebtedness, if after incurring such additional debt, our debt to equity ratio exceeds 1.65x. The NMFC Credit Facility requires that we not exceed a secured debt ratio of 0.70 to 1.00 at any time. We cannot assure you that we will be able to negotiate a change to our credit facilities to allow us to incur additional leverage or that any such an amendment will be available to us on favorable terms. An inability on our part to amend the contractual asset coverage limitation and access additional leverage could limit our ability to take advantage of the benefits described above related to our ability to incur additional leverage and could decrease our earnings, if any, which would have an adverse effect on our results of operations and the value of our shares of common stock. |  |  |  |  |  |  |  |  |
Reverse Repurchase Agreement Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may enter into reverse repurchase agreements, which are another form of leverage. We may enter into reverse repurchase agreements as part of our management of our investment portfolio. Under a reverse repurchase agreement, we will effectively pledge our assets as collateral to secure a short-term loan. Generally, the other party to the agreement makes the loan in an amount equal to a percentage of the fair value of the pledged collateral. At the maturity of the reverse repurchase agreement, the payor will be required to repay the loan and correspondingly receive back its collateral. While used as collateral, the assets continue to pay principal and interest which are for our benefit. Our use of reverse repurchase agreements, if any, involves many of the same risks involved in our use of leverage, as the proceeds from reverse repurchase agreements generally will be invested in additional securities. There is a risk that the market value of the securities acquired with the proceeds of a reverse repurchase agreement may decline below the price of the securities that we have sold but remain obligated to repurchase under the reverse repurchase agreement. In addition, there is a risk that the market value of the securities effectively pledged by us may decline. If a buyer of securities under a reverse repurchase agreement were to file for bankruptcy or experience insolvency, we may be adversely affected. Also, in entering into reverse repurchase agreements, we would bear the risk of loss to the extent that the proceeds of such agreements at settlement are more than the fair value of the underlying securities being pledged. In addition, due to the interest costs associated with reverse repurchase agreements transactions, our net asset value would decline, and, in some cases, we may be worse off than if such instruments had not been used. |  |  |  |  |  |  |  |  |
Debt Funding Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we are unable to obtain additional debt financing, or if our borrowing capacity is materially reduced, our business could be materially adversely affected. We may want to obtain additional debt financing, or need to do so upon maturity of our credit facilities, in order to obtain funds which may be made available for investments. Our $200.0 million in 2021A Unsecured Notes will mature on January 29, 2026, our $75.0 million in 2022A Unsecured Notes will mature on June 15, 2027, our $115.0 million in 8.250% Unsecured Notes will mature on November 15, 2028, our $300.0 million in 6.875% Unsecured Notes will mature on February 1, 2029 and our $300.0 million in 6.200% Unsecured Notes will mature on October 15, 2027. The SBA-guaranteed debentures have ten year maturities and will begin to mature on March 1, 2025. The Holdings Credit Facility and the 2022 Convertible Notes will mature on October 26, 2028 and October 15, 2025, respectively. The NMFC Credit Facility will mature on June 4, 2026 for Non-Extending Lenders and on September 28, 2029 for Extending Lenders. Of the $638.5 million in the NMFC Credit Facility, $111.4 million has been committed by Non-Extending Lenders and $527.1 million has been committed by Extending Lenders. If we are unable to increase, renew or replace any such facilities and enter into new debt financing facilities or other debt financing on commercially reasonable terms, our liquidity may be reduced significantly. In addition, if we are unable to repay amounts outstanding under any such facilities and are declared in default or are unable to renew or refinance these facilities, we may not be able to make new investments or operate our business in the normal course. These situations may arise due to circumstances that we may be unable to control, such as lack of access to the credit markets, a severe decline in the value of the U.S. dollar, an economic downturn or an operational problem that affects us or third parties, and could materially damage our business operations, results of operations and financial condition. |  |  |  |  |  |  |  |  |
Ability To Raise Capital Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may need to raise additional capital to grow. We may need additional capital to fund new investments and grow. We may access the capital markets periodically to issue equity securities. In addition, we may also issue debt securities or borrow from financial institutions in order to obtain such additional capital. Unfavorable economic conditions could increase our funding costs and limit our access to the capital markets or result in a decision by lenders not to extend credit to us. A reduction in the availability of new capital could limit our ability to grow. In addition, we are required to distribute at least 90.0% of our net ordinary income and net short-term capital gains in excess of net long-term capital losses, if any, to our stockholders to maintain our RIC status. As a result, these earnings will not be available to fund new investments. If we are unable to access the capital markets or if we are unable to borrow from financial institutions, we may be unable to grow our business and execute our business strategy fully, and our earnings, if any, could decrease, which could have an adverse effect on the value of our securities. |  |  |  |  |  |  |  |  |
Capital And Credit Markets Volatility Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | A renewed disruption in the capital markets and the credit markets could adversely affect our business. As a BDC, we must maintain our ability to raise additional capital for investment purposes. If we are unable to access the capital markets or credit markets, we may be forced to curtail our business operations and may be unable to pursue new investment opportunities. The capital markets and the credit markets have experienced extreme volatility in recent periods, and, as a result, there have been and will likely continue to be uncertainty in the financial markets in general. Disruptions in the capital markets in recent years increased the spread between the yields realized on risk-free and higher risk securities, resulting in illiquidity in parts of the capital markets. In addition, a prolonged period of market illiquidity may cause us to reduce the volume of loans that we originate and/or fund and adversely affect the value of our portfolio investments. Unfavorable economic conditions could also increase our funding costs, limit our access to the capital markets or result in a decision by lenders not to extend credit to us. These events could limit our investment originations, limit our ability to grow and negatively impact our operating results. Ongoing disruptive conditions in the financial industry and the impact of new legislation in response to those conditions could restrict our business operations and, consequently, could adversely impact our business, results of operations and financial condition. If the fair value of our assets declines substantially, we may fail to satisfy the asset coverage ratios imposed upon us by the 1940 Act and contained in the certain of the Unsecured Notes, Holdings Credit Facility, the 2022 Convertible Notes and the NMFC Credit Facility. Any such failure would result in a default under such indebtedness and otherwise affect our ability to issue senior securities, borrow under our credit facilities and pay distributions, which could materially impair our business operations. Our liquidity could be impaired further by our inability to access the capital or credit markets. For example, we cannot be certain that we will be able to renew our credit facilities as they mature or to consummate new borrowing facilities to provide capital for normal operations, including new originations, or reapply for SBIC licenses. In recent years, reflecting concern about the stability of the financial markets, many lenders and institutional investors have reduced or ceased providing funding to borrowers. This market turmoil and tightening of credit have led to increased market volatility and widespread reduction of business activity generally in recent years. In addition, adverse economic conditions due to these disruptive conditions could materially impact our ability to comply with the financial and other covenants in any existing or future credit facilities. If we are unable to comply with these covenants, this could materially adversely affect our business, results of operations and financial condition. |  |  |  |  |  |  |  |  |
Interest Rate Volatility Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Changes in interest rates may affect our cost of capital and net investment income. To the extent we borrow money to make investments, our net investment income depends, in part, upon the difference between the rate at which we borrow funds and the rate at which we invest those funds. As a result, a significant change in market interest rates may have a material adverse effect on our net investment income in the event we use debt to finance our investments. In periods of elevated interest rates, our cost of funds would increase, which could reduce our net investment income. Conversely, in periods of declining interest rates, we may earn less interest from our investments and our cost of funds will also decrease to a lesser extent, resulting in lower net investment income. We may use interest rate risk management techniques in an effort to limit our exposure to interest rate fluctuations. These techniques may include various interest rate hedging activities to the extent permitted by the 1940 Act. |  |  |  |  |  |  |  |  |
Small Business Association Regulations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | SBIC I and SBIC II are licensed by the SBA and are subject to SBA regulations. On August 1, 2014 and August 25, 2017, respectively, our wholly-owned direct and indirect subsidiaries, SBIC I and SBIC II, received licenses to operate as SBICs under the 1958 Act and are regulated by the SBA. The SBA places certain limitations on the financing terms of investments by SBICs in portfolio companies, regulates the types of financing an SBIC can provide, prohibits investing in small businesses with certain characteristics or in certain industries and requires capitalization thresholds that limit distributions to us. Compliance with SBA regulations may cause SBIC I and SBIC II to invest at less competitive rates in order to find investments that qualify under SBA regulations. The SBA regulations require, among other things, an annual periodic examination of a licensed SBIC by an SBA examiner to determine the SBIC's compliance with the relevant SBA regulations, and the performance of a financial audit by an independent auditor. If SBIC I and SBIC II fail to comply with applicable regulations, the SBA could, depending on the severity of the violation, limit or prohibit SBIC I's and SBIC II's use of the debentures, declare outstanding debentures immediately due and payable, and/or limit SBIC I and SBIC II from making new investments. In addition, the SBA could revoke or suspend SBIC I's or SBIC II's licenses for willful or repeated violation of, or willful or repeated failure to observe, any provision of the 1958 Act or any rule or regulation promulgated thereunder. These actions by the SBA would, in turn, negatively affect us because SBIC I and SBIC II are our wholly-owned direct and indirect subsidiaries. SBA-guaranteed debentures are non-recourse to us, have a ten year maturity, and may be prepaid at any time without penalty. Pooling of issued SBA-guaranteed debentures occurs in March and September of each year. The interest rate of SBA- guaranteed debentures is fixed at the time of pooling at a market-driven spread over ten year U.S. Treasury Notes. Leverage through SBA-guaranteed debentures is subject to required capitalization thresholds. Legislation adopted in 2018 raised the amount that any single SBIC may borrow to two tiers of leverage capped from $150.0 million to $175.0 million, subject to SBA approval, where each tier is equivalent to the SBIC's regulatory capital, which generally equates to the amount of equity capital in the SBIC. Currently, SBIC I and SBIC II operate under the prior $150.0 million cap. The amount of SBA-guaranteed debentures that SBICs under common control can have outstanding is $350.0 million, subject to SBA approval. |  |  |  |  |  |  |  |  |
Capital Funding Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Because we intend to distribute substantially all of our income to our stockholders to maintain our status as a RIC, we will continue to need additional capital to finance our growth. If additional funds are unavailable or not available on favorable terms, our ability to grow may be impaired. In order for us to qualify for the tax benefits available to RICs and to avoid payment of excise taxes, we intend to distribute to our stockholders substantially all of our annual taxable income. As a result of these requirements, we may need to raise capital from other sources to grow our business. As a BDC, we are required to meet a coverage ratio of total assets, less liabilities and indebtedness not represented by senior securities and excluding SBA-guaranteed debentures as permitted by exemptive relief obtained from the SEC, to total senior securities, which includes all of our borrowings with the exception of SBA-guaranteed debentures, of at least 150.0% (which means we can borrow $2 for every $1 of our equity). This requirement limits the amount that we may borrow. Since we continue to need capital to grow our investment portfolio, these limitations may prevent us from incurring debt and require us to raise additional equity at a time when it may be disadvantageous to do so. While we expect that we will be able to borrow and to issue additional debt securities and expect that we will be able to issue additional equity securities, which would in turn increase the equity capital available to us, we cannot assure you that debt and equity financing will be available to us on favorable terms, or at all. In addition, as a BDC, we generally are not permitted to issue equity securities at a price below then-current net asset value without stockholder approval. If additional funds are not available us, we may be forced to curtail or cease new investment activities, and our net asset value could decline. |  |  |  |  |  |  |  |  |
Regulated Investment Company Tax Treatment Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | SBIC I and SBIC II may be unable to make distributions to us that will enable us to meet or maintain our RIC tax treatment. In order for us to continue to qualify for tax benefits available to RICs and to minimize U.S. federal income tax, we generally must timely distribute to our stockholders, for each taxable year, at least 90.0% of our "investment company taxable income", which is generally our net ordinary income plus the excess of realized net short-term capital gains over realized net long-term capital losses, including investment company taxable income from SBIC I and SBIC II. We will be partially dependent on SBIC I and SBIC II for cash distributions to enable us to meet the RIC distribution requirements. SBIC I and SBIC II may be limited by SBA regulations governing SBICs from making certain distributions to us that may be necessary to maintain our tax treatment as a RIC. We may have to request a waiver of the SBA's restrictions for SBIC I and SBIC II to make certain distributions to maintain our RIC tax treatment. We cannot assure you that the SBA will grant such waiver and if SBIC I and SBIC II are unable to obtain a waiver, compliance with the SBA regulations may result in our income being subject to U.S. federal income tax imposed at corporate rates. |  |  |  |  |  |  |  |  |
Affiliate Transaction Restrictions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our ability to enter into transactions with our affiliates is restricted. As a BDC, we are prohibited under the 1940 Act from participating in certain transactions with certain of our affiliates without the prior approval of a majority of our independent directors and, in some cases, of the SEC. Any person that owns, directly or indirectly, 5.0% or more of our outstanding voting securities is an affiliate of ours for purposes of the 1940 Act. We are generally prohibited from buying or selling any securities (other than our securities) from or to an affiliate. The 1940 Act also prohibits us from participating in certain "joint" transactions with certain of our affiliates, including New Mountain Private Credit Fund, New Mountain Guardian IV BDC, L.L.C., New Mountain Guardian IV Income Fund, L.L.C., NMF SLF I, Inc. and other funds and accounts that the Investment Adviser manages, which could include investments in the same portfolio company (whether at the same or different times), without prior approval of independent directors and, in some cases, the SEC. If a person acquires more than 25.0% of our voting securities, we are prohibited from buying or selling any security (other than our securities) from or to such person or certain of that person's affiliates, or entering into prohibited joint transactions with such persons, absent the prior approval of the SEC. Similar restrictions limit our ability to transact business with our officers or directors or their affiliates. As a result of these restrictions, we may be prohibited from buying or selling any security (other than any security of which we are the issuer) from or to any portfolio company of a fund managed by any affiliate of the Investment Adviser, or entering into joint arrangement, such as certain co-investments with these companies or funds, without the prior approval of the SEC, which may limit the scope of investment opportunities that would otherwise be available to us. We rely on exemptive relief granted to the Investment Adviser and certain of its affiliates by the SEC that allows us to engage in co‑investment transactions with other affiliated funds of the Investment Adviser, subject to certain terms and conditions. However, while the terms of the exemptive relief require that the Investment Adviser will be given the opportunity to cause us to participate in certain transactions originated by affiliates of the Investment Adviser, the Investment Adviser may determine that we will not participate in those transactions and for certain other transactions (as set forth in guidelines approved by the Board) the Investment Adviser may not have the opportunity to cause us to participate. |  |  |  |  |  |  |  |  |
Investment Advisor Conflict Of Interest Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Investment Adviser has significant potential conflicts of interest with us and, consequently, your interests as stockholders which could adversely impact our investment returns. Our executive officers and directors, as well as the current or future investment professionals of the Investment Adviser, serve or may serve as officers, directors or principals of entities that operate in the same or a related line of business as we do or of investment funds managed by our affiliates. Accordingly, they may have obligations to investors in those entities, the fulfillment of which might not be in your interests as stockholders. The investment professionals of the Investment Adviser and/or New Mountain Capital employees that provide services pursuant to the Investment Management Agreement may manage other funds which may from time to time have overlapping investment objectives with our own and, accordingly, may invest in, whether principally or secondarily, asset classes similar to those targeted by us. If this occurs, the Investment Adviser may face conflicts of interest in allocating investment opportunities to us and such other funds. Although the investment professionals endeavor to allocate investment opportunities in a fair and equitable manner, it is possible that we may not be given the opportunity to participate in certain investments made by the Investment Adviser or persons affiliated with the Investment Adviser or that certain of these investment funds may be favored over us. When these investment professionals identify an investment, they may be forced to choose which investment fund should make the investment. While we may co-invest with investment entities managed by the Investment Adviser or its affiliates to the extent permitted by the 1940 Act and the rules and regulations thereunder, the 1940 Act imposes significant limits on co-investment. On October 8, 2019, the SEC issued the Exemptive Order, as amended by a subsequent order granted on August 30, 2022, which superseded a prior order issued on December 18, 2017, which permits us to co-invest in portfolio companies with certain funds or entities managed by the Investment Adviser or its affiliates in certain negotiated transactions where co-investing would otherwise be prohibited under the 1940 Act, subject to the conditions of the Exemptive Order. Pursuant to the Exemptive Order, we are permitted to co-invest with our affiliates if a “required majority” (as defined in Section 57(o) of the 1940 Act) of our independent directors make certain conclusions in connection with a co-investment transaction, including, but not limited to, that (1) the terms of the potential co-investment transaction, including the consideration to be paid, are reasonable and fair to us and our stockholders and does not involve overreaching by us or our stockholders on the part of any person concerned, and (2) the potential co-investment transaction is consistent with the interests of our stockholders and is consistent with our then- current investment objectives and strategies. If the Investment Adviser manages certain other affiliates in the future, we may co-invest on a concurrent basis with such other affiliates, subject to compliance with applicable regulations and regulatory guidance or an exemptive order from the SEC and our allocation procedures. In addition, we pay management and incentive fees to the Investment Adviser and reimburse the Investment Adviser for certain expenses it incurs. As a result, investors in our common stock invest in us on a “gross” basis and receive distributions on a “net” basis after our expenses. Also, the incentive fee payable to the Investment Adviser may create an incentive for the Investment Adviser to pursue investments that are riskier or more speculative than would be the case in the absence of such compensation arrangements. Any potential conflict of interest arising as a result of the arrangements with the Investment Adviser could have a material adverse effect on our business, results of operations and financial condition. |  |  |  |  |  |  |  |  |
Investment Committee, The Investment Advisor Or Its Affiliates With Non-Public Information Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Investment Committee, the Investment Adviser or its affiliates may, from time to time, possess material non-public information, limiting our investment discretion. The Investment Adviser’s investment professionals, Investment Committee or their respective affiliates may serve as directors of, or in a similar capacity with, companies in which we invest. In the event that material non-public information is obtained with respect to such companies, or we become subject to trading restrictions under the internal trading policies of those companies or as a result of applicable law or regulations, we could be prohibited for a period of time from purchasing or selling the securities of such companies, and this prohibition may have an adverse effect on us and our stockholders. |  |  |  |  |  |  |  |  |
Portfolio Valuation And Conflict Of Interest Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The valuation process for certain of our portfolio holdings creates a conflict of interest. Some of our portfolio investments are made in the form of securities that are not publicly traded. As a result, our board of directors determines the fair value of these securities in good faith. In connection with this determination, investment professionals from the Investment Adviser may provide our board of directors with portfolio company valuations based upon the most recent portfolio company financial statements available and projected financial results of each portfolio company. In addition, Steven B. Klinsky, a member of our board of directors, has an indirect pecuniary interest in the Investment Adviser. The participation of the Investment Adviser’s investment professionals in our valuation process, and the indirect pecuniary interest in the Investment Adviser by a member of our board of directors, could result in a conflict of interest as the Investment Adviser’s management fee is based, in part, on our gross assets and incentive fees are based, in part, on unrealized gains and losses. |  |  |  |  |  |  |  |  |
Conflicts Of Interest With Investment Advisor Or Its Affiliates Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Conflicts of interest may exist related to other arrangements with the Investment Adviser or its affiliates. We have entered into a royalty-free license agreement with New Mountain Capital under which New Mountain Capital has agreed to grant us a non-exclusive, royalty-free license to use the names "New Mountain" and "New Mountain Finance", as well as the NMF logo. In addition, we reimburse the Administrator for the allocable portion of overhead and other expenses incurred by the Administrator in performing its obligations to us under the Administration Agreement, such as, but not limited to, the allocable portion of the cost of our chief financial officer and chief compliance officer and their respective staffs. This could create conflicts of interest that our board of directors must monitor. |  |  |  |  |  |  |  |  |
Investment Management Agreement And Administration Agreement Related Party Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Investment Management Agreement with the Investment Adviser and the Administration Agreement with the Administrator were not negotiated on an arm’s length basis. The Investment Management Agreement and the Administration Agreement were negotiated between related parties. In addition, we may choose not to enforce, waive, or to enforce less vigorously, our respective rights and remedies under these agreements because of our desire to maintain our ongoing relationship with the Investment Adviser, the Administrator and their respective affiliates. Any such decision, however, could cause us to breach our fiduciary obligations to our stockholders. |  |  |  |  |  |  |  |  |
Investment Advisor Indemnification Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Investment Adviser’s liability is limited under the Investment Management Agreement, and we have agreed to indemnify the Investment Adviser against certain liabilities, which may lead the Investment Adviser to act in a riskier manner than it would when acting for its own account. Under the Investment Management Agreement, the Investment Adviser does not assume any responsibility other than to render the services called for under that agreement, and it is not responsible for any action of our board of directors in following or declining to follow the Investment Adviser’s advice or recommendations. Under the terms of the Investment Management Agreement, the Investment Adviser, its officers, members, personnel, any person controlling or controlled by the Investment Adviser are not liable for acts or omissions performed in accordance with and pursuant to the Investment Management Agreement, except those resulting from acts constituting gross negligence, willful misconduct, bad faith or reckless disregard of the Investment Adviser’s duties under the Investment Management Agreement. In addition, we have agreed to indemnify the Investment Adviser and each of its officers, directors, members, managers and employees from and against any claims or liabilities, including reasonable legal fees and other expenses reasonably incurred, arising out of or in connection with our business and operations or any action taken or omitted pursuant to authority granted by the Investment Management Agreement, except where attributable to gross negligence, willful misconduct, bad faith or reckless disregard of such person’s duties under the Investment Management Agreement. These protections may lead the Investment Adviser to act in a riskier manner than it would when acting for its own account. |  |  |  |  |  |  |  |  |
Investment Advisor Resignation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Investment Adviser can resign upon 60 days’ notice, and a suitable replacement may not be found within that time, resulting in disruptions in our operations that could adversely affect our business, results of operations and financial condition. Under the Investment Management Agreement, the Investment Adviser has the right to resign at any time upon 60 days’ written notice, whether a replacement has been found or not. If the Investment Adviser resigns, we may not be able to find a new investment adviser or hire internal management with similar expertise and ability to provide the same or equivalent services on acceptable terms within 60 days, or at all. If a replacement is not able to be found on a timely basis, our business, results of operations and financial condition and our ability to pay distributions are likely to be materially adversely affected and the market price of our common stock may decline. In addition, if we are unable to identify and reach an agreement with a single institution or group of executives having the expertise possessed by the Investment Adviser and its affiliates, the coordination of its internal management and investment activities is likely to suffer. Even if we are able to retain comparable management, whether internal or external, their integration into our business and lack of familiarity with our investment objective may result in additional costs and time delays that may materially adversely affect our business, results of operations and financial condition. |  |  |  |  |  |  |  |  |
Administrator Resignation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Administrator can resign upon 60 days’ notice from its role as Administrator under the Administration Agreement, and a suitable replacement may not be found, resulting in disruptions that could adversely affect our business, results of operations and financial condition. The Administrator has the right to resign under the Administration Agreement upon 60 days’ written notice, whether a replacement has been found or not. If the Administrator resigns, it may be difficult to find a new administrator or hire internal management with similar expertise and ability to provide the same or equivalent services on acceptable terms, or at all. If a replacement is not found quickly, our business, results of operations and financial condition, as well as our ability to pay distributions, are likely to be adversely affected, and the market price of our common stock may decline. In addition, the coordination of our internal management and administrative activities is likely to suffer if we are unable to identify and reach an agreement with a service provider or individuals with the expertise possessed by the Administrator. Even if a comparable service provider or individuals to perform such services are retained, whether internal or external, their integration into our business and lack of familiarity with our investment objective may result in additional costs and time delays that may materially adversely affect our business, results of operations and financial condition. |  |  |  |  |  |  |  |  |
Business Development Company Regulation Impact on Operating Flexibility Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we fail to operate as a BDC, our business and operating flexibility could be significantly reduced. We have elected to be regulated as a BDC under the 1940 Act. The 1940 Act imposes numerous constraints on the operations of BDCs. For example, BDCs are required to invest at least 70.0% of their total assets in qualifying assets such as U.S. private companies or thinly-traded U.S. public companies, cash, cash equivalents, U.S. government securities and other high quality debt investments that mature in one year or less. Failure to comply with the requirements imposed on BDCs by the 1940 Act could cause the SEC to bring an enforcement action against us and/or expose us to claims of private litigants. In addition, upon approval of a majority of our stockholders, we may elect to withdraw our election as a BDC. If we decide to withdraw our election, or if we otherwise fail to operate as a BDC, we may be subject to substantially greater regulation under the 1940 Act as a registered closed-end investment company. Compliance with these regulations would significantly decrease our operating flexibility and could significantly increase our cost of doing business. |  |  |  |  |  |  |  |  |
Investments In Qualifying Assets Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we do not invest a sufficient portion of our assets in qualifying assets, we could be precluded from investing in certain assets or could be required to dispose of certain assets, which could have a material adverse effect on our business, financial condition and results of operations. As a BDC, we are prohibited from acquiring any assets other than qualifying assets unless, at the time of and after giving effect to such acquisition, at least 70.0% of our total assets are qualifying assets. We may acquire in the future other investments that are not qualifying assets to the extent permitted by the 1940 Act. If we do not invest a sufficient portion of our assets in qualifying assets, we would be prohibited from investing in additional assets, which could have a material adverse effect on our business, financial condition and results of operations. Similarly, these rules could prevent us from making follow on investments in existing portfolio companies (which could result in the dilution of our position) or could require us to dispose of investments at inopportune times in order to come into compliance with the 1940 Act. If we need to dispose of these investments quickly, it may be difficult to dispose of such investments on favorable terms. For example, we may have difficulty in finding a buyer and, even if a buyer is found, we may have to sell the investments at a substantial loss. |  |  |  |  |  |  |  |  |
Limitation On Investment In Public Companies Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our ability to invest in public companies may be limited in certain circumstances. To maintain our status as a BDC, we are not permitted to acquire any assets other than qualifying assets specified in the 1940 Act unless, at the time the acquisition is made, at least 70.0% of our total assets are qualifying assets (with certain limited exceptions). Subject to certain exceptions for follow-on investments and distressed companies, an investment in an issuer that has outstanding securities listed on a national securities exchange may be treated as qualifying assets only if such issuer has a common equity market capitalization that is less than $250.0 million at the time of such investment. |  |  |  |  |  |  |  |  |
Business Development Company Regulation Impact On Investment Objectives And Strategies Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Regulations governing the operations of BDCs will affect our ability to raise additional equity capital as well as our ability to issue senior securities or borrow for investment purposes, any or all of which could have a negative effect on our investment objectives and strategies. Our business requires a substantial amount of capital. We may acquire additional capital from the issuance of senior securities, including borrowing under a credit facility or other indebtedness. In addition, we may also issue additional equity capital, which would in turn increase the equity capital available to us. However, we may not be able to raise additional capital in the future on favorable terms or at all. We may issue debt securities, preferred stock, and we may borrow money from banks or other financial institutions, which we refer to collectively as "senior securities", up to the maximum amount permitted by the 1940 Act. The 1940 Act permits us to issue senior securities in amounts such that our asset coverage, as defined in the 1940 Act, equals at least 150.0% after each issuance of senior securities (which means we can borrow $2 for every $1 of our equity). As a result of our SEC exemptive order, we are permitted to exclude the senior securities issued by SBIC I and SBIC II from the definition of senior securities in the 150.0% asset coverage ratio we are required to maintain under the 1940 Act. If our asset coverage ratio is not at least 150.0%, we would be unable to issue additional senior securities, and certain provisions of certain of our senior securities may preclude us from making distributions to our stockholders. For example, our 2021A Unsecured Notes and 2022A Unsecured Notes contain a covenant that prohibits us from declaring or paying a distribution to our stockholders unless we satisfy the asset coverage ratio immediately after the distribution, and the 8.250% Unsecured Notes contain a covenant that would be triggered if we declare or pay a distribution to our stockholders resulting in an asset coverage ratio of less than 150.0% for more than six consecutive months. If the value of our assets declines, we may be unable to satisfy this test. If that happens, we may be required to liquidate a portion of our investments and repay a portion of our indebtedness at a time when such sales may be disadvantageous. The following table summarizes our indebtedness as of December 31, 2024:
Borrowing |  | Maturity Date |  | Permitted Borrowing |  | Total Outstanding
|  |  |  | (in millions) |  | (in millions)
2021A Unsecured Notes |  | January 29, 2026 |  | N/A |  | $ | 200.0 |
2022A Unsecured Notes |  | June 15, 2027 |  | N/A |  | 75.0 |
8.250% Unsecured Notes |  | November 15, 2028 |  | N/A |  | 115.0 |
6.875% Unsecured Notes |  | February 1, 2029 |  | N/A |  | 300.0 |
6.200% Unsecured Notes |  | October 15, 2027 |  | N/A |  | 300.0 |
SBA-guaranteed debentures |  | Beginning March 1, 2025 |  | N/A |  | 300.0 |
Holdings Credit Facility |  | October 26, 2028 |  | $ | 730.0 |  |  | 294.4 |
2022 Convertible Notes |  | October 15, 2025 |  | N/A |  | 260.0 |
NMFC Credit Facility(1) |  | Beginning June 4, 2026(2) |  | 638.5 |  |  | 27.9 |
Unsecured Management Company Revolver |  | December 31, 2027 |  | 100.0 |  |  | — |
|  |  |  |  |  | $ | 1,872.3 |
(1)Under the NMFC Credit Facility, we may borrow in United States dollars or certain other permitted currencies. As of December 31, 2024, we had borrowings denominated in Euro ("EUR") of €16.5 million and in British Pound Sterling ("GBP") of £8.7 million that have been converted to U.S. dollars. (2)Of the $638.5 million in the NMFC Credit Facility, $111.4 million has been committed by Non-Extending Lenders and $527.1 million has been committed by Extending Lenders. The Non-Extending Lenders must be repaid on or before June 4, 2026 and the Extending Lenders must be repaid on or before September 28, 2029. N/A - not applicable We may also obtain capital through the issuance of additional equity capital. As a BDC, we generally are not able to issue or sell our common stock at a price below then-current net asset value per share. If our common stock trades at a discount to our net asset value per share, this restriction could adversely affect our ability to raise equity capital. We may, however, sell our common stock, or warrants, options or rights to acquire our common stock, at a price below our net asset value per share of the common stock if our board of directors and independent directors determine that such sale is in our best interests and the best interests of our stockholders, and our stockholders approve such sale. In any such case, the price at which our securities are to be issued and sold may not be less than a price that, in the determination of our board of directors, closely approximates the market value of such securities (less any underwriting commission or discount). If we raise additional funds by issuing more shares of our common stock, or if we issue senior securities convertible into, or exchangeable for, our common stock, the percentage ownership of our stockholders may decline and you may experience dilution. |  |  |  |  |  |  |  |  |
Referral Relationship Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our business model in the future may depend to an extent upon our referral relationships with private equity sponsors, and the inability of the investment professionals of the Investment Adviser to maintain or develop these relationships, or the failure of these relationships to generate investment opportunities, could adversely affect our business strategy. If the investment professionals of the Investment Adviser fail to maintain existing relationships or develop new relationships with other sponsors or sources of investment opportunities, we may not be able to grow our investment portfolio. In addition, individuals with whom the investment professionals of the Investment Adviser have relationships are not obligated to provide us with investment opportunities, and, therefore, there is no assurance that any relationships they currently or may in the future have will generate investment opportunities for us. |  |  |  |  |  |  |  |  |
Fluctuation Of Results Due To Nature Of the Business Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may experience fluctuations in our annual and quarterly results due to the nature of our business. We could experience fluctuations in our annual and quarterly operating results due to a number of factors, some of which are beyond our control, including the ability or inability of us to make investments in companies that meet our investment criteria, the interest rate payable on the debt securities acquired and the default rate on such securities, the level of our expenses, variations in and the timing of the recognition of realized and unrealized gains or losses, the degree to which we encounter competition in the markets in which we operate and general economic conditions. As a result of these factors, results for any period should not be relied upon as being indicative of performance in future periods. |  |  |  |  |  |  |  |  |
Changes Implemented By The Board Of Directors Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our board of directors may change our investment objective, operating policies and strategies without prior notice or stockholder approval, the effects of which may be adverse to your interests as stockholders. Our board of directors has the authority, except as otherwise provided in the 1940 Act, to modify or waive certain of our operating policies and strategies without prior notice and without stockholder approval. As a result, our board of directors may be able to change our investment policies and objectives without any input from our stockholders. However, absent stockholder approval, we may not change the nature of our business so as to cease to be, or withdraw our election to be regulated as, a BDC. Under Delaware law, we also cannot be dissolved without prior stockholder approval. We cannot predict the effect any changes to our current operating policies and strategies would have on our business, operating results and the market price of our common stock. Nevertheless, any such changes could adversely affect our business and impair our ability to make distributions to our stockholders. |  |  |  |  |  |  |  |  |
Federal Income Tax Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We will be subject to U.S. federal income tax imposed at corporate rates on all of our income if we are unable to maintain tax treatment as a RIC under Subchapter M of the Code, which would have a material adverse effect on our financial performance. Although we intend to continue to qualify annually as a RIC under Subchapter M of the Code, no assurance can be given that we will be able to maintain our RIC tax treatment. To maintain RIC tax treatment and be relieved of U.S. federal income taxes on income and gains distributed to our stockholders, we must meet the annual distribution, source-of-income and asset diversification requirements described below. •The Annual Distribution Requirement for a RIC generally is satisfied if we timely distribute (or are deemed to distribute) to our stockholders on an annual basis at least 90.0% of our net ordinary taxable income plus the excess of realized net short-term capital gains over realized net long-term capital losses, if any. Because we use debt financing, we are subject to an asset coverage ratio requirement under the 1940 Act, and we are subject to certain financial covenants contained in the Holdings Credit Facility and other debt financing agreements (as applicable). This asset coverage ratio requirement and these financial covenants could, under certain circumstances, restrict us from making distributions to our stockholders, which distributions are necessary for us to satisfy the Annual Distribution Requirement. If we are unable to obtain cash from other sources, and thus are unable to make sufficient distributions to our stockholders, we could fail to qualify for RIC tax treatment and thus become subject to U.S. federal income tax imposed at corporate rates (and any applicable state and local taxes). •The source-of-income requirement will be satisfied if at least 90.0% of our allocable share of our gross income for each year is derived from dividends and interest payments with respect to loans of certain securities, gains from the sale of stock or other securities, net income from certain “qualified publicly traded partnerships” (as defined in the Code) or other income derived with respect to our business of investing in such stock or securities. •The asset diversification requirement will be satisfied if we meet certain asset diversification requirements at the end of each quarter of our taxable year. To satisfy this requirement, (i) at least 50.0% of the value of our assets must consist of cash, cash equivalents, U.S. government securities, securities of other RICs, and other securities if such other securities of any one issuer do not represent more than 5.0% of the value of our assets or more than 10.0% of the outstanding voting securities of the issuer; and (ii) no more than 25.0% of the value of our assets can be invested in (a) the securities, other than U.S. government securities or securities of other RICs, of one issuer, (b) the securities, other than securities of other RICs of two or more issuers that are controlled, as determined under applicable Code rules, by us and that are engaged in the same or similar or related trades or businesses or (c) the securities of one or more “qualified publicly traded partnerships”. Failure to meet these requirements may result in us having to dispose of certain investments quickly in order to prevent the loss of our RIC status. Because most of our investments are intended to be in private companies, and therefore may be relatively illiquid, any such dispositions could be made at disadvantageous prices and could result in substantial losses. If we fail to maintain our tax treatment as a RIC for any reason, and we do not qualify for certain relief provisions under the Code, we would be subject to U.S. federal income tax imposed at corporate rates (and any applicable state and local taxes). In this event, the resulting tax liability could substantially reduce our net assets, the amount of income available for distribution and the amount of our distributions, which would have a material adverse effect on our financial performance. |  |  |  |  |  |  |  |  |
Current Tax Liability On Distributions Reinvested Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | You may have current tax liabilities on distributions you reinvest in our common stock. Under the dividend reinvestment plan, if you own shares of our common stock registered in your own name, you will have all cash distributions automatically reinvested in additional shares of our common stock unless you opt out of the dividend reinvestment plan by delivering notice by phone, internet or in writing to the plan administrator at least three days prior to the payment date of the next dividend or distribution. If you have not “opted out” of the dividend reinvestment plan, you will be deemed to have received, and be required to include income for U.S. federal income tax purposes, the amount reinvested in our common stock to the extent the amount reinvested was not a tax-free return of capital. As a result, you may have to use funds from other sources to pay your U.S. federal income tax liability on the value of the common stock received. |  |  |  |  |  |  |  |  |
Inability to Pay Distributions Or Decreased Distributions And Distributions May Be Return Of Capital Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may not be able to pay you distributions on our common stock, our distributions to you may not grow over time and a portion of our distributions to you may be a return of capital for U.S. federal income tax purposes. We intend to pay quarterly distributions to our stockholders out of assets legally available for distribution. We cannot assure you that we will continue to achieve investment results that will allow us to make a specified level of cash distributions or year-to-year increases in cash distributions. If we are unable to satisfy the asset coverage test applicable to us as a BDC, or if we violate certain covenants under the Unsecured Notes, the Holdings Credit Facility or the NMFC Credit Facility, our ability to pay distributions to our stockholders could be limited. All distributions are paid at the discretion of our board of directors and depend on our earnings, financial condition, maintenance of our RIC status, compliance with applicable BDC regulations, compliance with covenants under the Unsecured Notes, the Holdings Credit Facility and the NMFC Credit Facility, and such other factors as our board of directors may deem relevant from time to time. The distributions that we pay to our stockholders in a year may exceed our taxable income for that year and, accordingly, a portion of such distributions may constitute a return of capital or gain from sale or exchange of property for U.S. federal income tax purposes. |  |  |  |  |  |  |  |  |
Inability To Pay Distributions If Recognizing Taxable Income Without Receiving Cash Representing Such Income Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may have difficulty paying our required distributions if we recognize taxable income before or without receiving cash representing such income. For U.S. federal income tax purposes, we include in our taxable income our allocable share of certain amounts that we have not yet received in cash, such as original issue discount or accruals on a contingent payment debt instrument, which may occur if we receive warrants in connection with the origination of a loan or possibly in other circumstances or contracted PIK interest and dividends, which generally represents contractual interest added to the loan balance and due at the end of the loan term. Our allocable share of such original issue discount and PIK interest are included in our taxable income before we receive any corresponding cash payments. We also may be required to include in our taxable income our allocable share of certain other amounts that we will not receive in cash. Because in certain cases we may recognize taxable income before or without receiving cash representing such income, we may have difficulty making distributions to our stockholders that will be sufficient to enable us to meet the Annual Distribution Requirement necessary for us to qualify for tax treatment as a RIC. Accordingly, we may need to sell some of our assets at times and/or at prices that we would not consider advantageous. We may need to raise additional equity or debt capital, or we may need to forego new investment opportunities or otherwise take actions that are disadvantageous to our business (or be unable to take actions that are advantageous to our business) to enable us to make distributions to our stockholders that will be sufficient to enable us to meet the annual distribution requirement. If we are unable to obtain cash from other sources to enable us to meet the annual distribution requirement, we may fail to qualify for the U.S. federal income tax benefits allowable to RICs and, thus, become subject to a U.S. federal income tax imposed at corporate rates (and any applicable state and local taxes). |  |  |  |  |  |  |  |  |
Tax Issues Risk Regarding Below Investment Grade Securities Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Special tax issues regarding below investment grade securities We expect to invest in debt securities that are rated below investment grade by rating agencies or that would be rated below investment grade if they were rated. Investments in these types of instruments may present special tax issues for us. U.S. federal income tax rules are not entirely clear about issues such as when we may cease to accrue interest, original issue discount or market discount, when and to what extent deductions may be taken for bad debts or worthless instruments, how payments received on obligations in default should be allocated between principal and income and whether exchanges of debt obligations in a bankruptcy or workout context are taxable. These and other issues will be addressed by us, to the extent necessary, to preserve our status as a RIC and to distribute sufficient income to not become subject to U.S. federal income tax. |  |  |  |  |  |  |  |  |
Changes In Laws Or Regulations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Changes in laws or regulations governing our operations may adversely affect our business or cause us to alter our business strategy. Changes in the laws or regulations or the interpretations of the laws and regulations that govern BDCs, RICs or non-depository commercial lenders could significantly affect our operations and our cost of doing business. Our portfolio companies are subject to U.S. federal, state and local laws and regulations. New legislation may be enacted or new interpretations, rulings or regulations could be adopted, any of which could materially adversely affect our business, including with respect to the types of investments we are permitted to make, and your interests as stockholders potentially with retroactive effect. In addition, any changes to the laws and regulations governing our operations relating to permitted investments may cause us to alter our investment strategy in order to make available to ourselves new or different opportunities. These changes could result in material changes to our strategies which may result in our investment focus shifting from the areas of expertise of the Investment Adviser to other types of investments in which the Investment Adviser may have less expertise or little or no experience. Any such changes, if they occur, could have a material adverse effect on our business, results of operations and financial condition and, consequently, the value of your investment in us. Over the last several years, there has been an increase in regulatory attention to the extension of credit outside of the traditional banking sector, raising the possibility that some portion of the non-bank financial sector will be subject to new regulation. While it cannot be known at this time whether these regulations will be implemented or what form they will take, increased regulation of non-bank credit extension could negatively impact our operations, cash flows or financial condition, impose additional costs on us, intensify the regulatory supervision of us or otherwise adversely affect our business. |  |  |  |  |  |  |  |  |
Tax Reform Legislation Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We cannot predict how tax reform legislation will affect us, our investments, or our stockholders, and any such legislation could adversely affect our business. Legislative or other actions relating to taxes could have a negative effect on us. The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the Internal Revenue Service and the U.S. Treasury Department. Similarly, there are a number of proposals in Congress that would also modify the Code. The likelihood of any such legislation being enacted is uncertain, but new legislation and any U.S. Treasury regulations, administrative interpretations or court decisions interpreting such legislation could have adverse consequences, including significantly and negatively affect our ability to qualify for tax treatment as a RIC or otherwise impact the U.S. federal income tax consequences applicable to us and our stockholders of such qualification, or could have other adverse consequences. Stockholders are urged to consult with their tax advisor regarding tax legislative, regulatory, or administrative developments and proposals and their potential effect on an investment in our securities. |  |  |  |  |  |  |  |  |
Securities Litigation Or Shareholder Activism Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our business and operations could be negatively affected if we become subject to any securities litigation or shareholder activism, which could cause us to incur significant expense, hinder execution of investment strategy and impact our stock price. In the past, following periods of volatility in the market price of a company’s securities, securities class action litigation has often been brought against that company. Stockholder activism, which could take many forms or arise in a variety of situations, has been increasing in recent years. While we are currently not subject to any securities litigation or stockholder activism, due to the potential volatility of our stock price and for a variety of other reasons, we may in the future become the target of securities litigation or shareholder activism. Securities litigation and stockholder activism, including potential proxy contests, could result in substantial costs and divert the attention of our management and board of directors and resources from our business. Additionally, such securities litigation and stockholder activism could give rise to perceived uncertainties as to our future, adversely affect our relationships with service providers and make it more difficult to attract and retain qualified personnel. Also, we may be required to incur significant legal fees and other expenses related to any securities litigation or activist stockholder matters. Further, our stock price could be subject to significant fluctuation or otherwise be adversely affected by the events, risks and uncertainties of any securities litigation or stockholder activism. |  |  |  |  |  |  |  |  |
Global Climate Change Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The effect of global climate change may impact the operations and valuation of our portfolio companies. Climate change creates physical and financial risk and some of our portfolio companies may be adversely affected by climate change. For example, the needs of customers of energy companies vary with weather conditions, primarily temperature and humidity. To the extent weather conditions are affected by climate change, energy use could increase or decrease depending on the duration and magnitude of any changes. Increases in the cost of energy could adversely affect the cost of operations of our portfolio companies if the use of energy products or services is material to their business. A decrease in energy use due to weather changes may affect some of our portfolio companies’ financial condition through, for example, decreased revenues, which may, in turn, impact the valuation of such portfolio companies. Extreme weather conditions in general require more system backup, adding to costs, and can contribute to increased system stresses, including service interruptions. In December 2015 the United Nations adopted a climate accord (the "Paris Agreement") with the long-term goal of limiting global warming and the short-term goal of significantly reducing greenhouse gas emissions. The current presidential administration has announced the United States would cease participation. Additionally, the Inflation Reduction Act of 2022 included several measures designed to combat climate change, including restrictions on methane emissions. As a result, some of our portfolio companies may become subject to new or strengthened regulations or legislation, which could increase their operating costs and/or decrease their revenues, which may, in turn, impact their ability to make payments on our investments. |  |  |  |  |  |  |  |  |
Small Business Credit Availability Act Leverage Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The Small Business Credit Availability Act ("SBCA") allows us to incur additional leverage, which could increase the risk of investing in our securities. The SBCA amends the 1940 Act to permit a BDC to reduce the required minimum asset coverage ratio applicable to 150.0% (which means we can borrow $2 for every $1 of our equity), subject to certain requirements described therein. On April 12, 2018, our board of directors, including a "required majority" (as such term is defined in Section 57(o) of the 1940 Act) approved the application of the modified asset coverage requirements set forth in Section 61(a) of the 1940 Act, as amended by the SBCA, and recommended the submission of a proposal for stockholders to approve the application of the 150.0% minimum asset coverage ratio to us at a special meeting of stockholders, which was held on June 8, 2018. The stockholder proposal was approved by the required votes of our stockholders at such special meeting of stockholders, and thus we became subject to the 150.0% minimum asset coverage ratio on June 9, 2018. Changing the asset coverage ratio permits us to double our leverage, which results in increased leverage risk and increased expenses. Leverage magnifies the potential for loss on investments in our indebtedness and on invested equity capital. As we use leverage to partially finance our investments, you will experience increased risks of investing in our securities. If the value of our assets increases, then leveraging would cause the net asset value attributable to our common stock to increase more sharply than it would have had we not leveraged. Conversely, if the value of our assets decreases, leveraging would cause net asset value to decline more sharply than it otherwise would have had we not leveraged our business. Similarly, any increase in our income in excess of interest payable on the borrowed funds would cause our net investment income to increase more than it would without the leverage, while any decrease in our income would cause net investment income to decline more sharply than it would have had we not borrowed. Such a decline could negatively affect our ability to pay common stock dividends, scheduled debt payments or other payments related to our securities. Leverage is generally considered a speculative investment technique. Additionally, in June 2018, legislation amending the 1958 Act increased the individual leverage limit available to a single SBIC from $150.0 million to $175.0 million, subject to SBA approval. SBICs are generally eligible to borrow up to the individual leverage limit as long as the licensee satisfies the required amount of regulatory capital (equal to $75.0 million for SBIC I and SBIC II), has received a capital commitment from the SBA, and has been through an examination by the SBA subsequent to licensing. SBIC I and SBIC II operate under the prior $150.0 million cap. The maximum leverage available to a "family" of affiliated SBIC funds is $350.0 million, subject to SBA approval. We may issue additional SBIC debentures above the $300.0 million of SBA-guaranteed debentures currently permitted, pending application for and receipt of any additional SBIC licenses. If we incur this additional indebtedness in the future, your risk of an investment in our securities may increase. |  |  |  |  |  |  |  |  |
Public Traded Company Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We incur significant costs as a result of being a publicly traded company. As a publicly traded company, we incur legal, accounting and other expenses, which are paid by us, including costs associated with the periodic reporting requirements applicable to a company whose securities are registered under the Exchange Act, as well as additional corporate governance requirements, including requirements under the Sarbanes-Oxley Act of 2002, or the “Sarbanes-Oxley Act”, and other rules implemented by the SEC. |  |  |  |  |  |  |  |  |
Sarbanes-Oxley Act Compliance Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Efforts to comply with Section 404 of the Sarbanes-Oxley Act involve significant expenditures, and non-compliance with Section 404 of the Sarbanes-Oxley Act may adversely affect us and the market price of our common stock. We are subject to the Sarbanes-Oxley Act, and the related rules and regulations promulgated by the SEC. Under current SEC rules, since our fiscal year ending December 31, 2012, our management has been required to report on our internal control over financial reporting pursuant to Section 404 of the Sarbanes-Oxley Act, and rules and regulations of the SEC thereunder. We are required to review on an annual basis our internal control over financial reporting, and on a quarterly and annual basis to evaluate and disclose changes in our internal control over financial reporting. As a result, we expect to continue to incur additional expenses, which may negatively impact our financial performance and our ability to make distributions to our stockholders. This process also may result in a diversion of management’s time and attention. We cannot be certain as to the timing of completion of any evaluation, testing and remediation actions or the impact of the same on our operations, and we are not able to ensure that the process is effective or that our internal control over financial reporting is or will continue to be effective in a timely manner. In the event that we are unable to maintain or achieve compliance with Section 404 of the Sarbanes-Oxley Act and related rules, we and, consequently, the market price of our common stock may be adversely affected. |  |  |  |  |  |  |  |  |
Information Systems Failures Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our business is highly dependent on information systems and systems failures could significantly disrupt our business, which may, in turn, negatively affect the market price of our common stock and our ability to pay distributions. Our business is highly dependent on the communications and information systems of the Investment Adviser and its affiliates. Any failure or interruption of such systems could cause delays or other problems in our activities. This, in turn, could have a material adverse effect on our operating results and, consequently, negatively affect the market price of our common stock and our ability to pay distributions to our stockholders. In addition, because many of our portfolio companies operate and rely on network infrastructure and enterprise applications and internal technology systems for development, marketing, operational, support and other business activities, a disruption or failure of any or all of these systems in the event of a major telecommunications failure, cyber-attack, fire, earthquake, severe weather conditions or other catastrophic event could cause system interruptions, delays in product development and loss of critical data and could otherwise disrupt their business operations. |  |  |  |  |  |  |  |  |
Internal And External Cyber Threats Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We, and others in our industry, are the targets of malicious cyber activity, which we work hard to prevent. A successful cyber-attack, whether perpetrated by criminal or state-sponsored actors, against us or our service providers, or an accidental disclosure of non-public information, could have an adverse effect on our ability to communicate or conduct business, negatively impacting our operations and financial condition. This adverse effect can become particularly acute if those events affect our electronic data processing, transmission, storage, and retrieval systems, or impact the availability, integrity, or confidentiality of our data. We depend heavily upon computer systems to perform necessary business functions. Despite our implementation of a variety of security measures, our computer systems, networks, and data, like those of other companies, could be subject to unauthorized access, acquisition, use, alteration, or destruction, such as from the insertion of malware (including ransomware). physical and electronic break-ins or unauthorized tampering. If one or more of these events occurs, it could potentially jeopardize the confidential, proprietary, personal, and other information processed, stored in, and transmitted through our computer systems and networks. Such an attack could cause interruptions or malfunctions in our operations, which could result in financial losses, litigation, regulatory enforcement action and penalties, client dissatisfaction or loss, reputational damage, and increased costs associated with mitigation of damages and remediation. If unauthorized parties gain access to such information and technology systems, they may be able to steal, publish, delete or modify private and sensitive information, including nonpublic personal information related to stockholders (and their beneficial owners) and material nonpublic information. The systems we have implemented to manage risks relating to these types of events could prove to be inadequate and, if compromised, could become inoperable for extended periods of time, cease to function properly or fail to adequately secure private information. Breaches such as those involving covertly introduced malware, impersonation of authorized users and industrial or other espionage may not be identified even with sophisticated prevention and detection systems, potentially resulting in further harm and preventing them from being addressed appropriately. The failure of these systems or of disaster recovery plans for any reason could cause significant interruptions in our and our Investment Adviser’s operations and result in a failure to maintain the security, confidentiality or privacy of sensitive data, including personal information relating to stockholders, material nonpublic information and other sensitive information in our possession. A disaster or a disruption in the infrastructure that supports our business, including a disruption involving electronic communications or other services used by us or third parties with whom we conduct business, or directly affecting our headquarters, could have a material adverse impact on our ability to continue to operate our business without interruption. Our disaster recovery programs may not be sufficient to mitigate the harm that may result from such a disaster or disruption. In addition, insurance and other safeguards might only partially reimburse us for our losses, if at all. Third parties with which we do business are sources of cybersecurity or other technological risk. We outsource certain functions and these relationships allow for the storage and processing of our information, as well as client, counterparty, employee, and borrower information. While we engage in actions to reduce our exposure resulting from outsourcing, ongoing threats may result in unauthorized access, acquisition, use, alteration, destruction, or other cybersecurity incident that affects our data, resulting in increased costs and other consequences as described above. In addition, cybersecurity has become a top priority for regulators around the world, and some jurisdictions have enacted laws requiring companies to notify individuals of data security breaches involving certain types of personal data. If we fail to comply with the relevant laws and regulations, we could suffer financial losses, a disruption of our businesses, liability to investors, regulatory intervention or reputational damage. Additionally, there continues to be significant evolution and developments in the use of artificial intelligence technologies including generative artificial intelligence such as ChatGPT. We cannot fully determine the impact of such evolving technology to our business at this time. |  |  |  |  |  |  |  |  |
Cyber-Attacks Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We, the Investment Adviser and our portfolio companies are subject to risks associated with “phishing” and other cyber-attacks. Our business and the business of our portfolio companies relies upon secure information technology systems for data processing, storage and reporting. Despite careful security and controls design, implementation and updating, ours and our portfolio companies’ information technology systems could become subject to cyber-attacks. Cyber-attacks include, but are not limited to, gaining unauthorized access to digital systems (e.g., through “hacking”, malicious software coding, social engineering or “phishing” attempts) for purposes of misappropriating assets or sensitive information, corrupting data, or causing operational disruption. Cyber-attacks may also be carried out in a manner that does not require gaining unauthorized access, such as causing denial-of service attacks on websites (i.e., efforts to make network services unavailable to intended users). The Investment Adviser’s employees have been and expect to continue to be the target of fraudulent calls, emails and other forms of activities. The result of these incidents may include disrupted operations, misstated or unreliable financial data, liability for stolen information, misappropriation of assets, increased cybersecurity protection and insurance costs, litigation and damage to our business relationships, regulatory fines or penalties, or other adverse effects on our business, financial condition or results of operations. In addition, we may be required to expend significant additional resources to modify our protective measures and to investigate and remediate vulnerabilities or other exposures arising from operational and security risks related to cyber-attacks. The Investment Adviser’s and other service providers’ increased use of mobile and cloud technologies could heighten the risk of a cyber-attack as well as other operational risks, as certain aspects of the security of such technologies may be complex, unpredictable or beyond their control. The Investment Adviser’s and other service providers’ reliance on mobile or cloud technology or any failure by mobile technology and cloud service providers to adequately safeguard their systems and prevent cyber-attacks could disrupt their operations and result in misappropriation, corruption or loss of personal, confidential or proprietary information. In addition, there is a risk that encryption and other protective measures against cyber-attacks may be circumvented, particularly to the extent that new computing technologies increase the speed and computing power available. Additionally, remote working environments may be less secure and more susceptible to cyber-attacks, including phishing and social engineering attempts. Accordingly, the risks associated with cyber-attacks are heightened under current conditions. |  |  |  |  |  |  |  |  |
Risky Investments Portfolio Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our investments in portfolio companies may be risky, and we could lose all or part of any of our investments. Companies in which we invest could deteriorate as a result of, among other factors, an adverse development in their business, a change in the competitive environment or an economic downturn. As a result, companies which we expect to be stable may operate, or expect to operate, at a loss or have significant variations in operating results, may require substantial additional capital to support their operations or to maintain their competitive position, or may otherwise have a weak financial condition or be experiencing financial distress. In some cases, the success of our investment strategy will depend, in part, on the ability to restructure and effect improvements in the operations of a portfolio company. The activity of identifying and implementing restructuring programs and operating improvements at portfolio companies entails a high degree of uncertainty. There can be no assurance that any person (including us) will be able to successfully identify and implement such restructuring programs and improvements. Although the Investment Adviser’s investment strategy includes a focus on tight control of risk, there can be no assurance that the various risks of an investment will be successfully controlled or that losses can be avoided. Investments in small and middle market businesses are highly speculative and involve a high degree of risk of credit loss. These risks are likely to increase during volatile economic periods, such as the United States and many other economies have recently experienced. Among other things, these companies: •may have limited financial resources and may be unable to meet their obligations under their debt instruments that we hold, which may be accompanied by a deterioration in the value of any collateral and a reduction in the likelihood of us realizing any guarantees from subsidiaries or affiliates of our portfolio companies that we may have obtained in connection with our investment, as well as a corresponding decrease in the value of any equity components of our investments; •may have shorter operating histories, narrower product lines, smaller market shares and/or more significant customer concentrations than larger businesses, which tend to render them more vulnerable to competitors' actions and market conditions, as well as general economic downturns; •are more likely to depend on the management talents and efforts of a small group of persons; therefore, the death, disability, resignation or termination of one or more of these persons could have a material adverse impact on our portfolio company and, in turn, on us; •may be targets of cybersecurity or other technological risks; •generally have less predictable operating results, may from time to time be parties to litigation, may be engaged in rapidly changing businesses with products subject to a substantial risk of obsolescence; •may require substantial additional capital to support their operations, finance expansion or maintain their competitive position; and •generally have less publicly available information about their businesses, operations and financial condition. In addition, in the course of providing significant managerial assistance to certain of our eligible portfolio companies, certain of our officers and directors may serve as directors on the boards of such companies. To the extent that litigation arises out of our investments in these companies, our officers and directors may be named as defendants in such litigation, which could result in an expenditure of funds (through our indemnification of such officers and directors) and the diversion of management time and resources. |  |  |  |  |  |  |  |  |
Investment Strategy Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our investment strategy, which is focused primarily on privately held companies, presents certain challenges, including the lack of available information about these companies. We invest primarily in privately held companies. There is generally little public information about these companies, and, as a result, we must rely on the ability of the Investment Adviser to obtain adequate information to evaluate the potential returns from, and risks related to, investing in these companies. If we are unable to uncover all material information about these companies, we may not make a fully informed investment decision, and we may lose money on our investments. Also, privately held companies frequently have less diverse product lines and smaller market presence than larger competitors. They are, thus, generally more vulnerable to economic downturns and may experience substantial variations in operating results. These factors could adversely affect our investment returns. |  |  |  |  |  |  |  |  |
Investments In Investments Related Below Investment Grade Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our investments in securities rated below investment grade are speculative in nature and are subject to additional risk factors such as increased possibility of default, illiquidity of the security, and changes in value based on changes in interest rates. Our investments are almost entirely rated below investment grade or may be unrated, which are often referred to as “leveraged loans”, “high yield” or “junk” securities, and may be considered “high risk” compared to debt instruments that are rated investment grade. High yield securities are regarded as having predominantly speculative characteristics with respect to the issuer’s capacity to pay interest and repay principal in accordance with the terms of the obligations and involve major risk exposure to adverse conditions. In addition, high yield securities generally offer a higher current yield than that available from higher grade issues, but typically involve greater risk. These securities are especially sensitive to adverse changes in general economic conditions, to changes in the financial condition of their issuers and to price fluctuation in response to changes in interest rates. During periods of economic downturn or rising interest rates, issuers of below investment grade instruments may experience financial stress that could adversely affect their ability to make payments of principal and interest and increase the possibility of default. |  |  |  |  |  |  |  |  |
Limited Industry Portfolio Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our portfolio may be concentrated in a limited number of industries, which may subject us to a risk of significant loss if there is a downturn in a particular industry in which a number of our investments are concentrated. Our portfolio may be concentrated in a limited number of industries. For example, as of December 31, 2024, our investments in the software and the healthcare industries represented approximately 27.4% and 16.2%, respectively, of the fair value of our portfolio. A downturn in any particular industry in which we are invested could significantly impact the portfolio companies operating in that industry, and accordingly, the aggregate returns that we realize from our investment in such portfolio companies. Specifically, companies in the business services industry are subject to general economic downturns and business cycles, and will often suffer reduced revenues and rate pressures during periods of economic uncertainty. In addition, companies in the software industry often have narrow product lines and small market shares. Because of rapid technological change, the average selling prices of products and some services provided by software companies have historically decreased over their productive lives. As a result, the average selling prices of products and services offered by software companies in which we invest may decrease over time. If an industry in which we have significant investments suffers from adverse business or economic conditions, as these industries have to varying degrees, a material portion of our investment portfolio could be affected adversely, which, in turn, could adversely affect our financial position and results of operations. |  |  |  |  |  |  |  |  |
Unsecured Investments Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we make unsecured investments, those investments might not generate sufficient cash flow to service their debt obligations to us. We may make unsecured investments. Unsecured investments may be subordinated to other obligations of the obligor. Unsecured investments often reflect a greater possibility that adverse changes in the financial condition of the obligor or general economic conditions (including, for example, a substantial period of rising interest rates or declining earnings) or both may impair the ability of the obligor to make payment of principal and interest. If we make an unsecured investment in a portfolio company, that portfolio company may be highly leveraged, and its relatively high debt-to-equity ratio may increase the risk that its operations might not generate sufficient cash to service its debt obligations. |  |  |  |  |  |  |  |  |
Investments In Securities And Obligations Of Distressed And Bankrupt Issuers Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we invest in the securities and obligations of distressed and bankrupt issuers, we might not receive interest or other payments. From time to time, we may invest in other types of investments which are not our primary focus, including investments in the securities and obligations of distressed and bankrupt issuers, including debt obligations that are in covenant or payment default. Such investments generally are considered speculative. The repayment of defaulted obligations is subject to significant uncertainties. Defaulted obligations might be repaid only after lengthy workout or bankruptcy proceedings, during which the issuer of those obligations might not make any interest or other payments. |  |  |  |  |  |  |  |  |
Portfolio Company Default Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Defaults by our portfolio companies may harm our operating results. A portfolio company’s failure to satisfy financial or operating covenants imposed by us or other lenders could lead to defaults and, potentially, termination of its loans and foreclosure on its secured assets, which could trigger cross-defaults under other agreements and jeopardize a portfolio company’s ability to meet its obligations under the debt or equity securities that we hold. We may incur expenses to the extent necessary to seek recovery upon default or to negotiate new terms, which may include the waiver of certain financial covenants, with a defaulting portfolio company. In addition, lenders in certain cases can be subject to lender liability claims for actions taken by them when they become too involved in the borrower’s business or exercise control over a borrower. It is possible that we could become subject to a lender’s liability claim, including as a result of actions taken if we render significant managerial assistance to the borrower. Furthermore, if one of our portfolio companies were to file for bankruptcy protection, even though we may have structured our investment as senior secured debt, depending on the facts and circumstances, including the extent to which we provided managerial assistance to that portfolio company, a bankruptcy court might re-characterize our debt holding and subordinate all or a portion of our claim to claims of other creditors. |  |  |  |  |  |  |  |  |
Investment Liquidity Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The lack of liquidity in our investments may adversely affect our business. We invest, and will continue to invest, in companies whose securities are not publicly traded and whose securities will be subject to legal and other restrictions on resale or will otherwise be less liquid than publicly traded securities. The illiquidity of these investments may make it difficult for us to sell these investments when desired. In addition, if we are required or otherwise choose to liquidate all or a portion of our portfolio quickly, we may realize significantly less than the value at which we had previously recorded these investments. Our investments are usually subject to contractual or legal restrictions on resale or are otherwise illiquid because there is usually no established trading market for such investments. Because most of our investments are illiquid, we may be unable to dispose of them in which case we could fail to qualify as a RIC and/or a BDC, or we may be unable to do so at a favorable price, and, as a result, we may suffer losses. |  |  |  |  |  |  |  |  |
Price Declines and Illiquidity In Debt Markets Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Price declines and illiquidity in the corporate debt markets may adversely affect the fair value of our portfolio investments, reducing our net asset value through increased net unrealized depreciation. As a BDC, we are required to carry our investments at market value or, if no market quotation is readily available, at fair value as determined in good faith by our board of directors. As part of the valuation process, we may take into account the following types of factors, if relevant, in determining the fair value of our investments: •a comparison of the portfolio company's securities to publicly traded securities; •the enterprise value of a portfolio company; •the nature and realizable value of any collateral; •the portfolio company's ability to make payments and its earnings and discounted cash flow; •the markets in which the portfolio company does business; and •changes in the interest rate environment and the credit markets generally that may affect the price at which similar investments may be made in the future and other relevant factors. When an external event such as a purchase transaction, public offering or subsequent sale occurs, we will use the pricing indicated by the external event to corroborate our valuation. We will record decreases in the market values or fair values of our investments as unrealized depreciation. Declines in prices and liquidity in the corporate debt markets may result in significant net unrealized depreciation in our portfolio. The effect of all of these factors on our portfolio may reduce our net asset value by increasing net unrealized depreciation in our portfolio. Depending on market conditions, we could incur substantial realized losses and may suffer additional unrealized losses in future periods, which could have a material adverse effect on our business, financial condition, results of operations and cash flows. |  |  |  |  |  |  |  |  |
Follow-On Investment Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we are unable to make follow-on investments in our portfolio companies, the value of our investment portfolio could be adversely affected. We may not have the funds or ability to make additional investments in our portfolio companies or to fund our unfunded debt commitments. We expect that certain of our investments will take the form of unfunded commitments that we will be contractually obligated to fund on the demand of a borrower or other counterparty. We will not be able to control when, or if, these unfunded debt commitments are funded. Following an initial investment in a portfolio company, we may make additional investments in that portfolio company as “follow-on” investments, in order to, among other things, (i) increase or maintain in whole or in part our position as a creditor or equity ownership percentage in a portfolio company, (ii) exercise warrants, options or convertible securities that were acquired in the original or subsequent financing or (iii) preserve or enhance the value of our initial and overall investment. We may elect not to make follow-on investments or may otherwise lack sufficient funds to make these investments. We have the discretion to make follow-on investments, subject to the availability of capital resources, and the limitations of the 1940 Act. If we fail to make follow-on investments, the continued viability of a portfolio company and our initial investment or may, in some circumstances, result in a missed opportunity for us to increase our participation in a successful operation and our expected return on the investment may be reduced. Even if we have sufficient capital to make a desired follow-on investment, we may elect not to make a follow-on investment because of regulatory, tax, diversification or asset profiles or we may not want to increase our concentration of risk, either because we prefer other opportunities or because we are subject to BDC requirements that would prevent such follow-on investments or such follow-on investments would adversely impact our ability to qualify for or maintain our RIC status. |  |  |  |  |  |  |  |  |
Portfolio Company Debt Seniority Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our portfolio companies may incur debt that ranks equally with, or senior to, our investments in such companies. Our portfolio companies may incur debt that ranks equally with, or senior to, our investments in such companies. We invest in portfolio companies at all levels of the capital structure. Our portfolio companies may have, or may be permitted to incur, other debt that ranks equally with, or senior to, the debt in which we invest. By their terms, these debt instruments may entitle the holders to receive payment of interest or principal on or before the dates on which we are entitled to receive payments with respect to the debt instruments in which we invest. In addition, in the event of insolvency, liquidation, dissolution, reorganization or bankruptcy of a portfolio company, holders of debt instruments ranking senior to our investment in that portfolio company would typically be entitled to receive payment in full before we receive any distribution. After repaying the senior creditors, the portfolio company may not have any remaining assets to use for repaying its obligation to us. In the case of debt ranking equally with debt instruments in which we invest, we would have to share on an equal basis any distributions with other creditors holding such debt in the event of an insolvency, liquidation, dissolution, reorganization or bankruptcy of the relevant portfolio company. |  |  |  |  |  |  |  |  |
Disposition Of Investments Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The disposition of our investments may result in contingent liabilities. Most of our investments will involve private securities. In connection with the disposition of an investment in private securities, we may be required to make representations about the business and financial affairs of the portfolio company typical of those made in connection with the sale of a business. We may also be required to indemnify the purchasers of such investment to the extent that any such representations turn out to be inaccurate or with respect to certain potential liabilities. These arrangements may result in contingent liabilities that ultimately yield funding obligations that must be satisfied through our return of certain distributions previously made to us. |  |  |  |  |  |  |  |  |
Debt Investments Subordinated To Claims Of Others Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | There may be circumstances where our debt investments could be subordinated to claims of other creditors or we could be subject to lender liability claims. Even though we may have structured certain of our investments as senior loans, if one of our portfolio companies were to go bankrupt, depending on the facts and circumstances, including the extent to which we actually provided managerial assistance to that portfolio company, a bankruptcy court might re-characterize our debt investment and subordinate all or a portion of our claim to that of other creditors. We may also be subject to lender liability claims for actions taken by us with respect to a borrower’s business or instances where we exercise control over the borrower. It is possible that we could become subject to a lender’s liability claim, including as a result of actions taken in rendering significant managerial assistance. |  |  |  |  |  |  |  |  |
Second Priority Liens On Collateral Risks [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Second priority liens on collateral securing loans that we make to our portfolio companies may be subject to control by senior creditors with first priority liens. If there is a default, the value of the collateral may not be sufficient to repay in full both the first priority creditors and us. Certain loans to portfolio companies will be secured on a second priority basis by the same collateral securing senior secured debt of such companies. The first priority liens on the collateral will secure the portfolio company’s obligations under any outstanding senior debt and may secure certain other future debt that may be permitted to be incurred by the portfolio company under the agreements governing the loans. The holders of obligations secured by the first priority liens on the collateral will generally control the liquidation of and be entitled to receive proceeds from any realization of the collateral to repay their obligations in full before us. In addition, the value of the collateral in the event of liquidation will depend on market and economic conditions, the availability of buyers and other factors. There can be no assurance that the proceeds, if any, from the sale or sales of all of the collateral would be sufficient to satisfy the loan obligations secured by the second priority liens after payment in full of all obligations secured by the first priority liens on the collateral. If such proceeds are not sufficient to repay amounts outstanding under the loan obligations secured by the second priority liens, then we, to the extent not repaid from the proceeds of the sale of the collateral, will only have an unsecured claim against the portfolio company’s remaining assets, if any. The rights we may have with respect to the collateral securing the loans we make to our portfolio companies with senior debt outstanding may also be limited pursuant to the terms of one or more intercreditor agreements entered into with the holders of first priority senior debt. Under an intercreditor agreement, at any time obligations which have the benefit of the first priority liens are outstanding, any of the following actions that may be taken in respect of the collateral will be at the direction of the holders of the obligations secured by the first priority liens: the ability to cause the commencement of enforcement proceedings against the collateral, the ability to control the conduct of such proceedings, the approval of amendments to collateral documents; releases of liens on the collateral and waivers of past defaults under collateral documents. We may not have the ability to control or direct these actions, even if our rights are adversely affected. In addition, a bankruptcy court may choose not to enforce an intercreditor agreement or other agreement with creditors. Covenant-lite loans may offer us fewer protections than traditional investments. Some of our debt investments may have less restrictive covenant terms that provide us with fewer protections, called "covenant-lite" loans, that generally provide for fewer financial covenants on the borrower. In particular, borrowers under such covenant-lite loans may have greater flexibility in how they manage their financial condition. As a result, we may face challenges in recovering on such covenant-lite loans, to the extent they go into distress, and may lack options that would normally be available to us as a lender under more traditional debt structures. |  |  |  |  |  |  |  |  |
Lack Of Control Over Portfolio Companies Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We generally do not control our portfolio companies. Although we have taken and may in the future take controlling equity positions in our portfolio companies from time to time, we generally do not control most of our portfolio companies, even though we may have board representation or board observation rights, and our debt agreements may contain certain restrictive covenants that limit the business and operations of our portfolio companies. As a result, we are subject to the risk that a portfolio company may make business decisions with which we disagree and the management of such company may take risks or otherwise act in ways that do not serve our interests as debt investors. Due to the lack of liquidity of the investments that we typically hold in our portfolio companies, we may not be able to dispose of our investments in the event that we disagree with the actions of a portfolio company as readily as we would otherwise like to or at favorable prices which could decrease the value of our investments. |  |  |  |  |  |  |  |  |
Lack Of Influence Over Portfolio Company Day-To-Day Management And Personnel Retention Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We do not have influence over the day-to-day management of portfolio companies or their retention of effective personnel. Each portfolio company's day‑to‑day operations are the responsibility of such portfolio company's management team. Although the Investment Adviser is responsible for monitoring the performance of each portfolio investment, there can be no assurance that the existing management team, or any successor thereto, will be able to successfully operate the portfolio company in accordance with our plans and objectives. The success of each portfolio company depends in substantial part upon the skill and expertise of each portfolio company's management team. Additionally, portfolio companies will need to attract, retain and develop executives and members of their management teams. The market for executive talent is, notwithstanding general unemployment levels or developments within a particular industry, extremely competitive. There can be no assurance that portfolio companies will be able to attract, develop, integrate and retain suitable members of its management team and, as a result, such investment and we may be adversely affected thereby. |  |  |  |  |  |  |  |  |
Impact On Portfolio Companies Of Economic Recession, Downturn Or Government Spending Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Economic recessions, downturns or government spending cuts could impair our portfolio companies and harm our operating results. Many of our portfolio companies may be susceptible to economic slowdowns or recessions, and may be unable to repay its debt investments during these periods. Therefore, our non-performing assets are likely to increase, and the value of our portfolio is likely to decrease during these periods. Adverse economic conditions also may decrease the value of collateral securing some of our debt investments and the value of our equity investments. Economic slowdowns or recessions could lead to financial losses in our portfolio and a decrease in revenues, net income and assets. Unfavorable economic conditions also could increase our funding costs, limit our access to the capital markets or result in a decision by lenders not to extend credit to us. These events could prevent us from increasing investments and harm our operating results. |  |  |  |  |  |  |  |  |
Impact On Portfolio Companies Of Changes In Government Priorities, Spending Or Delays Or Reductions In Appropriations Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | A number of our portfolio companies provide services to the U.S. government. Changes in the U.S. government’s priorities and spending, or significant delays or reductions in appropriations of the U.S. government’s funds, could have a material adverse effect on the financial position, results of operations and cash flows of such portfolio companies. A number of our portfolio companies derive a substantial portion of their revenue from the U.S. government. Levels of the U.S. government’s spending in future periods are very difficult to predict and subject to significant risks. In addition, significant budgetary constraints may result in further reductions to projected spending levels. In particular, U.S. government expenditures are subject to the potential for automatic reductions, generally referred to as “sequestration.” Sequestration occurred during 2013, and may occur again in the future, resulting in significant additional reductions to spending by the U.S. government on both existing and new contracts as well as disruption of ongoing programs. Even if sequestration does not occur again in the future, we expect that budgetary constraints and ongoing concerns regarding the U.S. national debt will continue to place downward pressure on U.S. government spending levels. Due to these and other factors, overall U.S. government spending could decline, which could result in significant reductions to the revenues, cash flow and profits of our portfolio companies that provide services to the U.S. government. |  |  |  |  |  |  |  |  |
Impact Of Debt Investment Prepayments By Portfolio Companies Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Prepayments of our debt investments by our portfolio companies could adversely impact our results of operations and reduce our return on equity. We are subject to the risk that the investments we make in our portfolio companies may be repaid prior to maturity. When this occurs, subject to qualification for or maintenance of our RIC status, we will generally reinvest these proceeds in temporary investments, pending our future investment in new portfolio companies. These temporary investments will typically have substantially lower yields than the debt being prepaid and we could experience significant delays in reinvesting these amounts. Any future investment in a new portfolio company may also be at lower yields than the debt that was repaid. As a result, our results of operations could be materially adversely affected if one or more of our portfolio companies elect to prepay amounts owed to us. Additionally, prepayments could negatively impact our return on equity, which could result in a decline in the market price of our common stock. |  |  |  |  |  |  |  |  |
Gain On Equity Investments Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may not realize gains from our equity-related investments. When we invest in portfolio companies, we may acquire warrants or other equity-related securities of portfolio companies as well. We may also invest in equity-related securities directly. To the extent we hold equity investments, we will attempt to dispose of them and realize gains upon our disposition of them. However, the equity interests we receive may not appreciate in value and, in fact, may decline in value. As a result, we may not be able to realize gains from our equity interests, and any gains that we do realize on the disposition of any equity interests may not be sufficient to offset any other losses we experience. We also may be unable to realize any value if a portfolio company does not have a liquidity event, such as a sale of the business, recapitalization or public offering, which would allow us to sell the underlying equity interests. |  |  |  |  |  |  |  |  |
Due Diligence And Conduct Of Portfolio Companies Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Risks Relating to Due Diligence of and Conduct at Portfolio Companies Before making portfolio investments, the Investment Adviser typically conducts due diligence that they deem reasonable and appropriate based on the facts and circumstances applicable to each portfolio investment. Due diligence may entail evaluation of, among other things, important and complex business, financial, tax, accounting, environmental, social, governance and legal issues. When conducting due diligence and making an assessment regarding an investment, the Investment Adviser relies on the resources available to it, including information provided by the target of the investment and, in some circumstances, third‑party investigations and reports. The due diligence investigation that the Investment Adviser carries out with respect to any investment opportunity may not reveal or highlight all relevant facts that may be necessary or helpful in evaluating such investment opportunity. Moreover, such an investigation will not necessarily result in the portfolio investment being successful. There can be no assurance that attempts to provide downside protection with respect to portfolio investments will achieve their desired effect and potential investors should regard an investment in us as being speculative and having a high degree of risk. There can be no assurance that we will be able to detect or prevent irregular accounting, employee misconduct or other fraudulent practices during the due diligence phase or during our efforts to monitor the portfolio investment on an ongoing basis or that any risk management procedures implemented by us will be adequate. In the event of fraud by any portfolio company or any of its affiliates, we may suffer a partial or total loss of capital invested in that portfolio company. An additional concern is the possibility of material misrepresentation or omission on the part of the portfolio company or the seller. Such inaccuracy or incompleteness may adversely affect the value of our securities and/or instruments in such portfolio company. We rely upon the accuracy and completeness of representations made by portfolio companies and/or their former owners in the due diligence process to the extent reasonable when it makes our investments, but cannot guarantee such accuracy or completeness. Under certain circumstances, payments to us may be reclaimed if any such payment or distribution is later determined to have been a fraudulent conveyance or a preferential payment. Consultants, legal advisors, appraisers, accountants, investment banks and other third parties may be involved in the due diligence process and/or the ongoing operation of our portfolio companies to varying degrees depending on the type of investment. For example, certain asset management, finance, administrative and other similar functions may be outsourced to a third‑party service provider whose fees and expenses will be borne by such portfolio company or us and will not offset the management fee. Such involvement of third‑party advisors or consultants may present a number of risks primarily relating to the Investment Adviser's reduced control of the functions that are outsourced. In addition, if the Investment Adviser is unable to timely engage third‑party providers, their ability to evaluate and acquire more complex targets could be adversely affected. |  |  |  |  |  |  |  |  |
Actual Compared To Historical Performance Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Our performance may differ from our historical performance as our current investment strategy includes significantly more primary originations in addition to secondary market purchases. Historically, our investment strategy consisted primarily of secondary market purchases in debt securities. Over time, we have adjusted that investment strategy to also include significantly more primary originations. While loans that we originate and loans we purchase in the secondary market face many of the same risks associated with the financing of leveraged companies, we may be exposed to different risks depending on specific business considerations for secondary market purchases or origination of loans. Primary originations require substantially more time and resources for sourcing, diligencing and monitoring investments, which may consume a significant portion of our resources. Further, the valuation process for primary originations may be more cumbersome and uncertain due to the lack of comparable market quotes for the investment and would likely require more frequent review by a third-party valuation firm. This may result in greater costs for us and fluctuations in the quarterly valuations of investments that are primary originations. As a result, this strategy may result in different returns from these investments than the types of returns historically experienced from secondary market purchases of debt securities. |  |  |  |  |  |  |  |  |
Investment In Foreign Securities And Hedging Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We may be subject to additional risks if we invest in foreign securities. The 1940 Act generally requires that 70.0% of our investments be in issuers each of whom is, among other things, organized under the laws of, and has its principal place of business in the United States. Our investment strategy does not presently contemplate significant investments in securities of non-U.S. companies. However, we may desire to make such investments in the future, to the extent that such transactions and investments are permitted under the 1940 Act and any other applicable laws. We expect that these investments would focus on the same types of investments that we make in U.S. middle market companies and accordingly would be complementary to our overall strategy and enhance the diversity of our holdings. Investing in foreign companies could expose us to additional risks not typically associated with investing in U.S. companies. These risks include changes in exchange control regulations, political and social instability, expropriation, imposition of foreign taxes, less liquid markets and less available information than is generally the case in the U.S., higher transaction costs, less government supervision of exchanges, brokers and issuers, less developed bankruptcy laws, difficulty in enforcing contractual obligations, lack of uniform accounting and auditing standards and greater price volatility. Investments denominated in foreign currencies would be subject to the risk that the value of a particular currency will change in relation to one or more other currencies. Among the factors that may affect currency values are trade balances, the level of short-term interest rates, differences in relative values of similar assets in different currencies, long-term opportunities for investment and capital appreciation and political developments. We may employ hedging techniques to minimize these risks, but we can offer no assurance that we will, in fact, hedge currency risk, or that if we do, such strategies will be effective. Hedging using derivatives may impact investment performance. We may use over-the-counter (OTC) and cleared derivatives to hedge against fluctuations of the relative values of our portfolio positions from changes in market interest rates or currency exchange rates. Hedging against a decline in the values of our portfolio positions would not eliminate the possibility of fluctuations in the values of such positions or prevent losses if the values of the positions declined. However, such hedging could establish other positions designed to gain from those same developments, thereby offsetting the decline in the value of such portfolio positions. Hedging transactions may limit the opportunity for gain if the values of the underlying portfolio positions increased. Moreover, it might not be possible to hedge against an exchange rate or interest rate fluctuation that was so generally anticipated that we would not be able to enter into a hedging transaction at an acceptable price. If we choose to engage in hedging transactions, there can be no assurances that we will achieve the intended benefits of such transactions and, depending on the degree of exposure such transactions could create, such transactions may expose us to risk of loss. While we may enter into derivatives transactions to seek to reduce currency exchange rate and interest rate risks, unanticipated changes in currency exchange rates or interest rates could result in poorer overall investment performance than if we had not engaged in any such hedging transactions. In addition, the degree of correlation between price movements of the instruments used in a hedging strategy and price movements in the portfolio positions being hedged could vary. Moreover, for a variety of reasons, we might not seek to establish a perfect correlation between the hedging instruments and the portfolio holdings being hedged. Any imperfect correlation could prevent us from achieving the intended hedge and expose us to risk of loss. In addition, it might not be possible to hedge fully or perfectly against currency fluctuations affecting the value of securities denominated in non-U.S. currencies because the value of those securities would likely fluctuate as a result of factors not related to currency fluctuations. Our ability to enter into transactions involving derivatives and unfunded commitment transactions may be limited. In 2020, the SEC adopted Rule 18f-4 under the 1940 Act, which relates to the use of derivatives and other transactions that create future payment or delivery obligations by BDCs (and other funds that are registered investment companies). Under Rule 18f-4, for which compliance was required beginning in August 2022, BDCs that use derivatives are subject to a value-at-risk leverage limit, certain derivatives risk management program and testing requirements and requirements related to board reporting. These new requirements apply unless the BDC qualifies as a “limited derivatives user,” as defined in Rule 18f-4. A BDC that enters into reverse repurchase agreements or similar financing transactions could either (i) comply with the asset coverage requirements of Section 18, as modified by Section 61 of the 1940 Act, when engaging in reverse repurchase agreements or (ii) choose to treat such agreements as derivatives transactions under Rule 18f-4. In addition, under Rule 18f-4, a BDC may enter into an unfunded commitment agreement that is not a derivatives transaction, such as an agreement to provide financing to a portfolio company, if the BDC has a reasonable belief, at the time it enters into such an agreement, that it will have sufficient cash and cash equivalents to meet its obligations with respect to all of its unfunded commitment agreements, in each case as it becomes due. If the BDC cannot meet this requirement, it is required to treat the unfunded commitment as a derivatives transaction subject to the aforementioned requirements of Rule 18f-4. We qualify as a “limited derivatives user” for purposes of Rule 18f-4 and as a result the requirements applicable to us under Rule 18f-4 may limit our ability to use derivatives and enter into certain other financial contracts. However, if we fail to qualify as a limited derivatives user and become subject to the additional requirements under Rule 18f-4, compliance with such requirements may increase cost of doing business, which could have a material adverse effect on our business, financial condition, results of operations, and cash flows. Valuing OTC derivatives may be less certain than actively traded financial instruments. In general, valuing OTC derivatives is less certain than valuing actively traded financial instruments such as exchange traded futures contracts and securities or cleared swaps because, for OTC derivatives, the price and terms on which such OTC derivatives are entered into or can be terminated are individually negotiated, and those prices and terms may not reflect the best price or terms available from other sources. In addition, while market makers and dealers generally quote indicative prices or terms for entering into or terminating OTC contracts, they typically are not contractually obligated to do so, particularly if they are not a party to the transaction. As a result, it may be difficult to obtain an independent value for an outstanding OTC derivatives transaction. Our rights under an OTC derivative may be restricted by regulations. Regulations adopted by global prudential regulators that are now in effect require certain prudentially regulated entities and certain of their affiliates and subsidiaries (including swap dealers) to include in their derivatives contracts and certain other financial contracts terms that delay or restrict the rights of counterparties to terminate such contracts, foreclose upon collateral, exercise other default rights or restrict transfers of credit support in the event that the prudentially regulated entity and/or its affiliates are subject to certain types of resolution or insolvency proceedings. Similar regulations and laws have been adopted in non-U.S. jurisdictions that may apply to any of our counterparties that located in those jurisdictions. It is possible that these new requirements, as well as potential additional resulted government regulation, could adversely affect our ability to terminate existing derivatives contracts, exercise default rights, or satisfy obligations owed to us with collateral received under such contracts. The use of OTC derivatives may expose us to early termination risk, which could result in significant losses. OTC derivatives do not have uniform terms. An OTC derivatives counterparty may have the right to close out our position due to the occurrence of certain events (for example, if a counterparty is unable to hedge its obligations to us, or if we defaults on certain terms of the OTC swaps agreement, or if there is a material decline in our NAV on a particular day) and request immediate payment of amounts owed by us under the agreement. If the level of our NAV has a dramatic intraday move, the terms of our OTC derivatives document may permit the counterparty to early close out a transaction with us at a price calculated by the counterparty that, in good faith, represents such counterparty’s loss, which may not represent fair market value. An OTC derivatives counterparty may also have the right to close out our position for no reason, in some cases with same day notice. |  |  |  |  |  |  |  |  |
Market Price Of Common Stock Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | The market price of our common stock may fluctuate significantly. The market price and liquidity of the market for shares of our common stock may be significantly affected by numerous factors, some of which are beyond our control and may not be directly related to our operating performance. These factors include: •price and volume fluctuations in the overall stock market or in the market for BDCs from time to time; •investor demand for shares of our common stock; •significant volatility in the market price and trading volume of securities of registered closed-end management investment companies, BDCs or other financial services companies, which is not necessarily related to the operating performance of these companies; •the inability to raise equity capital; •our inability to borrow money or deploy or invest our capital; •fluctuations in interest rates; •any shortfall in revenue or net income or any increase in losses from levels expected by investors or securities analysts; •operating performance of companies comparable to us; •changes in regulatory policies or tax guidelines with respect to RICs or BDCs; •our loss of status as or ability to operate as a BDC; •our failure to qualify as a RIC, loss of RIC status or ability to operate as a RIC; •actual or anticipated changes in our earnings or fluctuations in our operating results; •changes in the value of our portfolio of investments; •general economic conditions, trends and other external factors; •departures of key personnel; or •loss of a major source of funding. In addition, we are required to continue to meet certain listing standards in order for our common stock and, from time to time, other securities, to remain listed on the NASDAQ Global Select Market ("NASDAQ"). If we were to be delisted by NASDAQ, the liquidity of our common stock would be materially impaired. |  |  |  |  |  |  |  |  |
Investment In Entity Common Stock Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Investing in our common stock may involve an above average degree of risk. The investments we may make may result in a higher amount of risk, volatility or loss of principal than alternative investment options. These investments in portfolio companies may be highly speculative and aggressive, and therefore, an investment in our common stock may not be suitable for investors with lower risk tolerance. |  |  |  |  |  |  |  |  |
Common Stock Price Related To Substantial Sales Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Sales of substantial amounts of our common stock in the public market may have an adverse effect on the market price of our common stock. Sales of substantial amounts of our common stock could materially adversely affect the prevailing market prices for our common stock. If substantial amounts of our common stock were sold, this could impair our ability to raise additional capital through the sale of securities should we desire to do so. |  |  |  |  |  |  |  |  |
Common Stock Price Related To Limitations On Takeover Attempt Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Certain provisions of our certificate of incorporation and bylaws, as well as aspects of the Delaware General Corporation Law, could deter takeover attempts and have an adverse impact on the price of our common stock. Our certificate of incorporation and bylaws as well as the Delaware General Corporation Law contain provisions that may have the effect of discouraging a third party from making an acquisition proposal for us. Among other things, our certificate of incorporation and bylaws: •provide for a classified board of directors, which may delay the ability of our stockholders to change the membership of a majority of our board of directors; •authorize the issuance of "blank check" preferred stock that could be issued by our board of directors to thwart a takeover attempt; •do not provide for cumulative voting; •provide that vacancies on the board of directors, including newly created directorships, may be filled only by a majority vote of directors then in office; •provide that our directors may be removed only for cause; •require supermajority voting to effect certain amendments to our certificate of incorporation and bylaws; and •require stockholders to provide advance notice of new business proposals and director nominations under specific procedures. These anti-takeover provisions may inhibit a change in control in circumstances that could give the holders of our common stock the opportunity to realize a premium over the market price for our common stock. Certain of the the Unsecured Notes, Holdings Credit Facility and the NMFC Credit Facility also include covenants that, among other things, restrict our ability to dispose of assets, incur additional indebtedness, make restricted payments, create liens on assets, make investments, make acquisitions and engage in mergers or consolidations. The Unsecured Notes (excluding the 8.250% Unsecured Notes), the Holdings Credit Facility and the NMFC Credit Facility also include change of control provisions that accelerate the indebtedness (or require prepayment of such indebtedness) under these agreements in the event of certain change of control events. |  |  |  |  |  |  |  |  |
Common Stock Trading At A Discount To Net Asset Value Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Shares of our common stock have traded at a discount from net asset value and may do so in the future. Shares of BDCs have frequently traded at a market price that is less than the net asset value that is attributable to those shares. In part as a result of adverse economic conditions and increasing pressure within the financial sector of which we are a part, our common stock has at times traded below our net asset value per share since our IPO on May 19, 2011. Our shares could once again trade at a discount to net asset value. The possibility that our shares of common stock may trade at a discount from net asset value over the long term is separate and distinct from the risk that our net asset value will decrease. We cannot predict whether shares of our common stock will trade above, at or below our net asset value. If our common stock trades below our net asset value, we will generally not be able to issue additional shares of our common stock without first obtaining the approval for such issuance from our stockholders and our independent directors. If additional funds are not available to us, we could be forced to curtail or cease our new lending and investment activities, and our net asset value could decrease and our level of distributions could be impacted. |  |  |  |  |  |  |  |  |
Inability To Pay Distributions Or Decreased Distributions Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | You may not receive distributions or our distributions may decline or may not grow over time. None of us, the Investment Adviser or their respective affiliates can provide any assurance whatsoever that we will be successful in choosing, making and realizing investments in any particular portfolio company or portfolio companies. There is no assurance that we will be able to generate returns for our investors or that the returns will be commensurate with the risks of investing in the type of companies and transactions described herein. While we expect to make regular distributions of income, there can be no assurance that any stockholder will receive any distribution from us. Partial or complete sales, transfers or other dispositions of portfolio investments which may result in a return of capital or the realization of gains, if any, are generally not expected to occur for a number of years after an investment is made. Accordingly, an investment in us should only be considered by persons for whom a speculative, illiquid and long‑term investment is an appropriate component of a larger investment program and who can afford a loss of their entire investment. Past performance of investment entities associated with New Mountain Capital and its affiliates is not necessarily indicative of future results. There can be no assurance that we will achieve comparable results or that our performance objectives will be achieved. In particular, we do not expect to replicate the historical performance of New Mountain Capital's investments, or those of certain affiliates that have also elected to be regulated as a BDC, including New Mountain Private Credit Fund, New Mountain Guardian IV BDC, L.L.C., New Mountain Guardian IV Income Fund, L.L.C., and NMF SLF Inc. In addition, our investment strategies may differ from those of New Mountain Capital or its affiliates. We, as a BDC and as a RIC, are subject to certain regulatory restrictions that do not apply to New Mountain Capital or certain of its affiliates. We are generally not permitted to invest in any portfolio company in which New Mountain Capital or any of its affiliates currently have an investment or to make any co‑investments with New Mountain Capital or its affiliates, except to the extent permitted by the 1940 Act, or pursuant to previously obtained exemptive orders. This may adversely affect the pace at which we make investments. |  |  |  |  |  |  |  |  |
Discretion Over Use Of Proceeds From Offering Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | We will have broad discretion over the use of proceeds of any offering made pursuant to our prospectus. We will have significant flexibility in applying the proceeds of any offering of our securities. We will also pay operating expenses, and may pay other expenses such as due diligence expenses of potential new investments, from net proceeds of such offerings. Our ability to achieve our investment objective may be limited to the extent that the net proceeds of the offerings, pending full investment, are used to pay operating expenses. In addition, we can provide you no assurance that any offering will be successful, or that by increasing the size of our available equity capital, our aggregate expenses, and correspondingly, our expense ratio, will be lowered. |  |  |  |  |  |  |  |  |
Diluted Shareholder Interest Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Your interest in NMFC may be diluted if you do not fully exercise your subscription rights in any rights offering. In the event we issue subscription rights to purchase shares of our common stock, stockholders who do not fully exercise their rights should expect that they will, at the completion of the offer, own a smaller proportional interest in NMFC than would otherwise be the case if they fully exercised their rights. We cannot state precisely the amount of any such dilution in share ownership because we do not know at this time what proportion of the shares will be purchased as a result of the offer. |  |  |  |  |  |  |  |  |
Volatility Of Common Stock If Preferred Stock Is Issued Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | If we issue preferred stock, the net asset value and market value of our common stock will likely become more volatile. We do not currently have any plans to issue preferred stock. However, to the extent that we do issue preferred stock in the future, we cannot assure you that the issuance of preferred stock would result in a higher yield or return to the holders of our common stock. The issuance of preferred stock would likely cause the net asset value and market price of the common stock to become more volatile. If the dividend rate on the preferred stock were to approach the net rate of return on our investment portfolio, the benefit of leverage to the holders of the common stock would be reduced. If the dividend rate on the preferred stock were to exceed the net rate of return on our portfolio, the leverage would result in a lower rate of return to the holders of common stock than if we had not issued preferred stock. Any decline in the net asset value of our investments would be borne entirely by the holders of common stock. Therefore, if the market value of our portfolio were to decline, the leverage would result in a greater decrease in net asset value to the holders of common stock than if we were not leveraged through the issuance of preferred stock. This greater net asset value decrease would also tend to cause a greater decline in the market price for the common stock. We might be in danger of failing to maintain the required asset coverage of the preferred stock or of losing our ratings, if any, on the preferred stock or, in an extreme case, our current investment income might not be sufficient to meet the dividend requirements on the preferred stock. In order to counteract such an event, we might need to liquidate investments in order to fund a redemption of some or all of the preferred stock. In addition, we would pay (and the holders of common stock would bear) all costs and expenses relating to the issuance and ongoing maintenance of the preferred stock, including higher advisory fees if our total return exceeds the dividend rate on the preferred stock. Holders of preferred stock may have different interests and rights than holders of common stock and may at times have disproportionate influence over our affairs. |  |  |  |  |  |  |  |  |
Ability To Elect Board Of Directors Members For Preferred Stock Holders Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Risk Factors [Table Text Block] |  |  |  |  |  |  |  |  |  | Holders of any preferred stock we might issue would have the right to elect members of our board of directors and class voting rights on certain matters. In accordance with the 1940 Act, holders of any preferred stock we might issue, voting separately as a single class, would have the right to elect two members of our board of directors at all times and in the event dividends become two full years in arrears would have the right to elect a majority of the directors until such arrearage is completely eliminated. In addition, preferred stockholders have class voting rights on certain matters, including changes in fundamental investment restrictions and conversion to open-end status, and accordingly can veto any such changes. Restrictions imposed on the declarations and payment of dividends or other distributions to the holders of our common stock and preferred stock, both by the 1940 Act and by requirements imposed by rating agencies, if any, or the terms of our credit facilities, if any, might impair our ability to maintain our tax treatment as a RIC for U.S. federal income tax purposes. While we would intend to redeem our preferred stock to the extent necessary to enable us to distribute our income as required to maintain our tax treatment as a RIC, there can be no assurance that such actions could be effected in time to meet the tax requirements. |  |  |  |  |  |  |  |  |
Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 531,500,000 | $ 511,500,000 | $ 145,000,000.0 | $ 90,000,000.0 |
Senior Securities Coverage per Unit |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,774 | $ 1,812 | $ 2,408 | $ 2,593 |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Interest Rate, Current [Percent] |  |  |  |  |  |  |  |  |  | 6.60% |  |  |  |  |  |  |  |  |
SBA-Guaranteed Debentures [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Interest Rate, Current [Percent] |  |  |  |  |  |  |  |  |  | 2.70% |  |  |  |  |  |  |  |  |
Holdings Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 294,400,000 |  |  |  | $ 515,100,000 |  |  |  | $ 294,400,000 | $ 515,100,000 | $ 450,200,000 | $ 661,600,000 | $ 512,600,000 | $ 619,000,000.0 | $ 545,300,000 | $ 312,400,000 | $ 333,500,000 | $ 419,300,000
Senior Securities Coverage per Unit |  | $ 1,867 |  |  |  | $ 1,875 |  |  |  | $ 1,867 | $ 1,875 | $ 1,807 | $ 1,740 | $ 1,814 | $ 1,774 | $ 1,812 | $ 2,408 | $ 2,593 | $ 2,341
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Interest Rate, Current [Percent] |  |  |  |  |  |  |  |  |  | 7.50% |  |  |  |  |  |  |  |  |
2022 Convertible Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 260,000,000.0 |  |  |  | $ 260,000,000.0 |  |  |  | $ 260,000,000.0 | $ 260,000,000.0 |  |  |  | $ 200,000,000.0 |  |  |  |
Senior Securities Coverage per Unit |  | $ 1,867 |  |  |  | $ 1,875 |  |  |  | $ 1,867 | $ 1,875 |  |  |  | $ 1,774 |  |  |  |
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Interest Rate, Current [Percent] |  |  |  |  |  |  |  |  |  | 7.50% |  |  |  |  |  |  |  |  |
NMFC Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 27,900,000 |  |  |  | $ 36,800,000 |  |  |  | $ 27,900,000 | $ 36,800,000 | $ 165,500,000 | $ 188,500,000 | $ 60,000,000.0 | $ 40,400,000 | $ 127,200,000 | $ 122,500,000 | $ 10,000,000.0 | $ 90,000,000.0
Senior Securities Coverage per Unit |  | $ 1,867 |  |  |  | $ 1,875 |  |  |  | $ 1,867 | $ 1,875 | $ 1,807 | $ 1,740 | $ 1,814 | $ 1,774 | $ 1,812 | $ 2,408 | $ 2,593 | $ 2,341
General Description of Registrant [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Interest Rate, Current [Percent] |  |  |  |  |  |  |  |  |  | 7.00% |  |  |  |  |  |  |  |  |
Unsecured Notes, Excluding 8.250% Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 875,000,000.0 |  |  |  | $ 391,500,000 |  |  |  | $ 875,000,000.0 | $ 391,500,000 |  |  |  |  |  |  |  |
Senior Securities Coverage per Unit |  | $ 1,867 |  |  |  | $ 1,875 |  |  |  | $ 1,867 | $ 1,875 |  |  |  |  |  |  |  |
Eight Point Two Five Percentage Notes Due Two Thousand Twenty Eight [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  | $ 115,000,000.0 |  |  |  | $ 115,000,000.0 |  |  |  | $ 115,000,000.0 | $ 115,000,000.0 |  |  |  |  |  |  |  |
Senior Securities Coverage per Unit |  | $ 1,867 |  |  |  | $ 1,875 |  |  |  | $ 1,867 | $ 1,875 |  |  |  |  |  |  |  |
Senior Securities Average Market Value per Unit |  |  |  |  |  |  |  |  |  | $ 24.26 | $ 25.88 |  |  |  |  |  |  |  |
DB Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  | $ 186,400,000 |  |  |  |  | $ 186,400,000 | $ 244,000,000.0 | $ 230,000,000.0 | $ 57,000,000.0 | $ 186,400,000 | $ 226,300,000 |  |  |
Senior Securities Coverage per Unit |  |  |  |  |  | $ 1,875 |  |  |  |  | $ 1,875 | $ 1,807 | $ 1,740 | $ 1,814 | $ 1,774 | $ 1,812 |  |  |
NMNLC Credit Facility II [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  | $ 2,900,000 |  |  |  |  | $ 2,900,000 |  |  |  | $ 3,800,000 | $ 15,200,000 |  |  |
Senior Securities Coverage per Unit |  |  |  |  |  | $ 1,875 |  |  |  |  | $ 1,875 |  |  |  | $ 1,774 | $ 1,812 |  |  |
2018 Convertible Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  |  |  |  |  |  |  | $ 201,200,000 | $ 201,200,000 | $ 115,000,000.0 | $ 116,800,000 | $ 201,200,000 |  |  |
Senior Securities Coverage per Unit |  |  |  |  |  |  |  |  |  |  |  | $ 1,807 | $ 1,740 | $ 1,814 | $ 1,774 | $ 1,812 |  |  |
Unsecured Notes, Excluding 5.75% Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  |  |  |  |  |  |  | $ 401,500,000 | $ 401,500,000 | $ 285,000,000.0 |  |  |  |  |
Senior Securities Coverage per Unit |  |  |  |  |  |  |  |  |  |  |  | $ 1,807 | $ 1,740 | $ 1,814 |  |  |  |  |
5.75% Unsecured Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  |  |  |  |  |  |  | $ 51,800,000 | $ 51,800,000 | $ 51,800,000 |  |  |  |  |
Senior Securities Coverage per Unit |  |  |  |  |  |  |  |  |  |  |  | $ 1,807 | $ 1,740 | $ 1,814 |  |  |  |  |
Senior Securities Average Market Value per Unit |  |  |  |  |  |  |  |  |  |  |  | $ 24.50 | $ 25.60 | $ 24.70 |  |  |  |  |
2014 Convertible Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Financial Highlights [Abstract] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Securities Amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 155,300,000 |  |  | $ 155,300,000 | $ 155,300,000 | $ 115,000,000.0
Senior Securities Coverage per Unit |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,814 |  |  | $ 2,408 | $ 2,593 | $ 2,341

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