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Summary of Significant Accounting Policies - Additional Information (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2023 USD ($) Loan Equipment	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) Equipment Loan
Disclosure Of Summary Of Significant Accounting Policies [Line Items]
Fair value of companies investment percentage	99.70%
Market index of investment securities	$ 0
Maturity period description	original maturity of three months or less
Cash and cash equivalents	$ 8,344,000		$ 10,612,000
Restricted cash	$ 0		0
Escrow Distribution period	1 year
Escrow receivable balance	$ 2,400,000		2,400,000
Payments receivable	56,900,000		$ 59,900,000
Interest income	$ 300,000	$ 0
Debt security payment due	90 days
Number of portfolio companies loans | Loan	2		2
Number of portfolio companies equipment financing | Equipment	2		2
Non accrual cost	$ 49,200,000		$ 49,200,000
Fair value	$ 23,900,000		$ 17,800,000
Fair value of debt investment portfolio	2.30%		1.70%
Debt instrument percentage	6.00%
Investment percentage	16.90%	15.70%
Percentage of net tax- exempt income	90.00%
Uncertain tax position	$ 0		$ 0
Nondeductible federal excise tax	4.00%
Ordinary income percentage	98.00%
Capital gain net income percentage	98.20%
Excise tax	4.00%
Goldman Sachs Financial Square Government Institutional Fund
Disclosure Of Summary Of Significant Accounting Policies [Line Items]
Cash and cash equivalents	$ 5,400,000		$ 5,600,000
Minimum
Disclosure Of Summary Of Significant Accounting Policies [Line Items]
Investment percentage	90.00%

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