Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Cost of the investment.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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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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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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The effective interest rate at the end of the reporting period.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Represents the total combined commitment amount for funding of joint venture.

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Represents the company commitment amount for funding of joint venture.

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Represents the increase (decrease) in company commitment amount for funding of joint venture.

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Represents the number of companies in the portfolio.

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Represents the fixe largest investments by aggregate principal amount.

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Represents the largest single investment by aggregate principal amount in a single portfolio company.

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Represents the borrowing balance threshold for applicable interest rate.

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INVESTMENTS - WHF STRS Ohio Senior Loan Fund LLC (Details) $ in Thousands			1 Months Ended	9 Months Ended	12 Months Ended
	Mar. 11, 2022 USD ($)	Jul. 15, 2021	Jul. 31, 2019	Sep. 30, 2022 USD ($) company	Dec. 31, 2021 USD ($)	Mar. 10, 2022 USD ($)	Feb. 28, 2022 USD ($)	Jan. 27, 2021 USD ($)	Jul. 19, 2019 USD ($)	Jan. 14, 2019 USD ($)
Schedule of Investments [Line Items]
Investments				$ 764,554	$ 819,208
Cost of investment				773,406	831,960
Available				88,899	43,363
Amortized Cost, credit facility				430,992	475,958
LIBOR or SOFR \| Minimum [Member]
Schedule of Investments [Line Items]
Term of interest			3 years
LIBOR or SOFR \| Maximum [Member]
Schedule of Investments [Line Items]
Term of interest			6 years
Subordinated Notes
Schedule of Investments [Line Items]
Investments				167	167
Cost of investment				167	167
Equity (excluding STRS JV)
Schedule of Investments [Line Items]
Investments				48,059	38,159
Cost of investment				$ 46,193	$ 36,991
STRS JV
Schedule of Investments [Line Items]
Combined investment commitment in joint venture										$ 125,000
Investment commitment in joint venture							$ 100,000			75,000
Increase in investment commitment in joint venture							$ 25,000
Economic ownership (as a percent)				66.67%	60.00%		66.67%
Investments				$ 306,392	$ 273,523
Portfolio companies \| company				28
Largest single investment				$ 20,086	23,483
Five largest investments				77,439	83,057
STRS JV \| STRS JV Credit Facility
Schedule of Investments [Line Items]
Maximum borrowing limit	$ 225,000			225,000	175,000			$ 175,000	$ 125,000
Variable interest rate (as a percent)		2.35%
Available	168,750					$ 131,250
Borrowings greater than	$ 175,000
Amortized Cost, credit facility				$ 151,127	$ 146,782
Effective interest rate (as a percent)				3.30%	2.50%
STRS JV \| STRS JV Credit Facility \| SOFR
Schedule of Investments [Line Items]
Variable interest rate (as a percent)	2.50%			2.50%
Borrowings greater than				$ 175,000
STRS JV \| STRS JV Credit Facility \| CDOR
Schedule of Investments [Line Items]
Maximum borrowing limit				$ 175,000
Variable interest rate (as a percent)				2.35%	2.35%
STRS JV \| Subordinated Notes
Schedule of Investments [Line Items]
Investment commitment in joint venture							$ 80,000
Cost of investment				$ 80,000	$ 60,000
STRS JV \| Equity (excluding STRS JV)
Schedule of Investments [Line Items]
Investment commitment in joint venture							$ 20,000
Cost of investment				$ 20,000	$ 15,000
STRS JV \| STRS Ohio
Schedule of Investments [Line Items]
Investment commitment in joint venture										$ 50,000
Economic ownership (as a percent)				33.33%	40.00%		33.33%