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Investment Company, Expense Ratio Before Fee Waiver And Reimbursements

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Investment Company, Expense Ratio Including Fee Waiver And Reimbursements

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Investment Company, Ratio To Average Net Assets

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Per share or unit amount of distribution to shareholders. Includes, but is not limited to, dividend and capital gain. Excludes distribution for tax return of capital.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit amount of realized and unrealized gain (loss) on investment.

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Per share or unit amount of investment income (loss) and realized and unrealized gain (loss) on investment.

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Per share or unit amount, after investment expense, of dividend and interest investment income (loss).

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Percentage of investment income (loss) to average net assets.

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Percentage increase (decrease) in fund net asset value, assuming reinvestment of dividends and capital gain distributions.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Average amount outstanding of long-term debt.

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Net asset value per share or per unit of investments in certain entities that calculate net asset value per share. Includes, but is not limited to, by unit, membership interest, or other ownership interest. Investment includes, but is not limited to, investment in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. Excludes fair value disclosure.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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Financial Highlights (Details) $ / shares in Units, € in Thousands, £ in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2022 GBP (£) shares	Sep. 30, 2022 EUR (€) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2021 GBP (£) shares	Dec. 31, 2021 EUR (€) shares
Investment Company, Financial Highlights [Roll Forward]
Net asset value, beginning balance (in dollars per share) \| $ / shares			$ 13.49	$ 12.62
Net investment income (in dollars per share) \| $ / shares			0.94	0.91
Net realized and unrealized (losses) gains (in dollars per share) \| $ / shares			(0.33)	0.63
Total net increase (in dollars per share) \| $ / shares			0.61	1.54
Distributions declared to stockholders from net investment income (in dollars per share) \| $ / shares			(0.90)	(0.90)
Net asset value, ending balance (in dollars per share) \| $ / shares	$ 13.20	$ 13.26	13.20	13.26
Per share market value (in dollars per share) \| $ / shares	$ 11.53	$ 13.31	$ 11.53	$ 13.31
Total return based on market value			(9.64%)	25.41%
Total return based on net asset value			4.54%	12.42%
Shares outstanding at end of period (in shares) \| shares	100,937,026	96,906,988	100,937,026	96,906,988	100,937,026	100,937,026	97,907,441	97,907,441	97,907,441
Average weighted shares outstanding for the period (in shares) \| shares	100,830,075	96,906,988	99,955,432	96,854,474
Average net assets for the period			$ 1,348,479	$ 1,253,263
Ratio to average net assets:
Net investment income			9.27%	9.48%
Total expenses, before waivers/reimbursements			12.85%	13.35%
Total expenses, net of waivers/reimbursements			12.50%	12.15%
Asset coverage ratio	179.28%	183.99%	179.28%	183.99%	179.28%	179.28%
Portfolio turnover			14.38%	25.47%
Common stock issuances (in dollars per share) \| $ / shares			$ 0.01	$ 0.00
Unsecured Notes
Ratio to average net assets:
Average debt outstanding	$ 539,870	$ 511,500	$ 525,456	$ 518,333
SBA-guaranteed debentures
Ratio to average net assets:
Average debt outstanding	300,000	300,000	300,000	300,000
Convertible Notes
Ratio to average net assets:
Average debt outstanding	201,250	201,250	201,250	201,250
Holdings Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Credit facility outstanding balance	630,663		630,663				$ 545,263
Holdings Credit Facility \| Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Average debt outstanding	607,585	483,131	580,699	467,570
DB Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Credit facility outstanding balance	186,400		186,400				226,300
DB Credit Facility \| Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Average debt outstanding	199,442	198,938	217,817	209,417
NMFC Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Credit facility outstanding balance	127,210		127,210		£ 22,850	€ 700	127,192	£ 16,400	€ 0
NMFC Credit Facility \| Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Average debt outstanding	171,850	$ 117,146	156,303	122,537
NMNLC Credit Facility II \| Revolving Credit Facility
Ratio to average net assets:
Credit facility outstanding balance	$ 2,934		2,934				$ 15,200
NMNLC Credit Facility II \| Credit Facility \| Revolving Credit Facility
Ratio to average net assets:
Average debt outstanding			$ 8,939	$ 1,533