$FSEN
FS Specialty Lending Fund Stock $fsen

$fsen Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000162828024011529 Filed on March 15, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$47.21M		$83.95M
YoY Change	175.18%		16.39%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization
YoY Change
% of Gross Profit
Operating Expenses
YoY Change
Operating Profit
YoY Change
Interest Expense	$9.084M		$23.70M
YoY Change	-27.89%		-57.47%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income
YoY Change
Income Tax			$0.00
% Of Pretax Income
Net Earnings	$18.11M	-$36.56M	-$121.2M
YoY Change	-155.63%	-220.88%	-165.68%
Net Earnings / Revenue	38.36%		-144.36%
Basic Earnings Per Share	$0.04	-$0.08	-$0.27
Diluted Earnings Per Share	$0.04	-$0.08	-$0.27
COMMON SHARES
Basic Shares Outstanding	455.5M shares	455.5M shares	454.4M shares
Diluted Shares Outstanding	455.5M shares	455.5M shares	454.4M shares

Balance Sheet

Concept	2024 Q1	2023 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$186.9M	$486.1M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment
YoY Change
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$2.047B	$2.060B
YoY Change	-6.96%	-19.51%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities
YoY Change
LONG-TERM LIABILITIES
Long-Term Debt
YoY Change
Other Long-Term Liabilities
YoY Change
Total Long-Term Liabilities
YoY Change
TOTAL LIABILITIES
Total Short-Term Liabilities
Total Long-Term Liabilities
Total Liabilities	$468.7M	$497.5M
YoY Change	-3.87%	-38.2%
SHAREHOLDERS EQUITY
Retained Earnings	-$1.608B	-$1.624B
YoY Change	8.32%	12.95%
Common Stock	$456.0K	$456.0K
YoY Change	0.66%	1.11%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$1.579B	$1.562B
YoY Change
Total Liabilities & Shareholders Equity	$2.047B	$2.060B
YoY Change	-6.96%	-19.51%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$18.11M	-$36.56M	-$121.2M
YoY Change	-155.63%	-220.88%	-165.68%
Depreciation, Depletion And Amortization
YoY Change
Cash From Operating Activities	-$264.3M		$436.5M
YoY Change	-197.55%		-11.59%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions
YoY Change
Other Investing Activities
YoY Change
Cash From Investing Activities
YoY Change
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-$29.29M		-$425.4M
YoY Change	-90.68%		825.26%
NET CHANGE
Cash From Operating Activities	-$264.3M		$436.5M
Cash From Investing Activities
Cash From Financing Activities	-$29.29M		-$425.4M
Net Change In Cash	-$293.6M		$11.10M
YoY Change	580.29%		-97.52%
FREE CASH FLOW
Cash From Operating Activities	-$264.3M		$436.5M
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-12-31
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	814-00841
CY2023	dei	Entity Registrant Name EntityRegistrantName	FS Specialty Lending Fund
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	27-6822130
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	201 Rouse Boulevard
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	Philadelphia
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	PA
CY2023	dei	City Area Code CityAreaCode	215
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CY2023	dei	Security12g Title Security12gTitle	Common Shares of Beneficial Interest, par value$0.001 per share
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CY2022Q4	us-gaap	Preferred Stock Value PreferredStockValue	0	usd
CY2023Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.001
CY2022Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.001
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	700000000	shares
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	700000000	shares
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	455506155	shares
CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	455506155	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	451465673	shares
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	451465673	shares
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	456000	usd
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	451000	usd
CY2023Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	3185784000	usd
CY2022Q4	us-gaap	Additional Paid In Capital AdditionalPaidInCapital	3191293000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1624185000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1437996000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	1562055000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	1753748000	usd
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	2059557000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	2558781000	usd
CY2023Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.43
CY2022Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.88
CY2023	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	157722000	usd
CY2022	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	184967000	usd
CY2021	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	150707000	usd
CY2023	us-gaap	Management Fee Expense ManagementFeeExpense	35377000	usd
CY2022	us-gaap	Management Fee Expense ManagementFeeExpense	44559000	usd
CY2021	us-gaap	Management Fee Expense ManagementFeeExpense	41561000	usd
CY2023	us-gaap	Administrative Fees Expense AdministrativeFeesExpense	6087000	usd
CY2022	us-gaap	Administrative Fees Expense AdministrativeFeesExpense	5626000	usd
CY2021	us-gaap	Administrative Fees Expense AdministrativeFeesExpense	5713000	usd
CY2023	us-gaap	Noninterest Expense Transfer Agent And Custodian Fees NoninterestExpenseTransferAgentAndCustodianFees	3206000	usd
CY2022	us-gaap	Noninterest Expense Transfer Agent And Custodian Fees NoninterestExpenseTransferAgentAndCustodianFees	2985000	usd
CY2021	us-gaap	Noninterest Expense Transfer Agent And Custodian Fees NoninterestExpenseTransferAgentAndCustodianFees	2918000	usd
CY2023	us-gaap	Professional Fees ProfessionalFees	588000	usd
CY2022	us-gaap	Professional Fees ProfessionalFees	731000	usd
CY2021	us-gaap	Professional Fees ProfessionalFees	692000	usd
CY2023	us-gaap	Interest Expense InterestExpense	23698000	usd
CY2022	us-gaap	Interest Expense InterestExpense	55716000	usd
CY2021	us-gaap	Interest Expense InterestExpense	54122000	usd
CY2023	us-gaap	Trustee Fees TrusteeFees	667000	usd
CY2022	us-gaap	Trustee Fees TrusteeFees	742000	usd
CY2021	us-gaap	Trustee Fees TrusteeFees	787000	usd
CY2023	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	4494000	usd
CY2021	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	3094000	usd
CY2023	us-gaap	Investment Company Expense After Reduction Of Fee Waiver And Reimbursement InvestmentCompanyExpenseAfterReductionOfFeeWaiverAndReimbursement	73776000	usd
CY2021	us-gaap	Investment Company Expense After Reduction Of Fee Waiver And Reimbursement InvestmentCompanyExpenseAfterReductionOfFeeWaiverAndReimbursement	107448000	usd
CY2023	us-gaap	Net Investment Income NetInvestmentIncome	83946000	usd
CY2022	us-gaap	Net Investment Income NetInvestmentIncome	72122000	usd
CY2021	us-gaap	Net Investment Income NetInvestmentIncome	43259000	usd
CY2023	us-gaap	Investment Income Operating Tax Expense Benefit InvestmentIncomeOperatingTaxExpenseBenefit	2583000	usd
CY2022	us-gaap	Investment Income Operating Tax Expense Benefit InvestmentIncomeOperatingTaxExpenseBenefit	2353000	usd
CY2021	us-gaap	Investment Income Operating Tax Expense Benefit InvestmentIncomeOperatingTaxExpenseBenefit	0	usd
CY2023	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	81363000	usd
CY2022	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	69769000	usd
CY2021	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	43259000	usd
CY2023	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	1048000	usd
CY2023	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	0	usd
CY2022	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-929000	usd
CY2023	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	698000	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-698000	usd
CY2021	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	36000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	-45000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	-12000	usd
CY2023	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-202546000	usd
CY2022	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	114733000	usd
CY2021	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	162616000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	184502000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	205875000	usd
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.27
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.27
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	443768738	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	443768738	shares
CY2023	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	81363000	usd
CY2022	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	69769000	usd
CY2023	us-gaap	Realized Gain Loss Investment Derivative And Foreign Currency Transaction Price Change Operating After Tax RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingAfterTax	-58376000	usd
CY2022	us-gaap	Realized Gain Loss Investment Derivative And Foreign Currency Transaction Price Change Operating After Tax RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingAfterTax	33467000	usd
CY2021	us-gaap	Realized Gain Loss Investment Derivative And Foreign Currency Transaction Price Change Operating After Tax RealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionPriceChangeOperatingAfterTax	-273467000	usd
CY2023	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	-144904000	usd
CY2022	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	82009000	usd
CY2021	us-gaap	Unrealized Gain Loss On Investments UnrealizedGainLossOnInvestments	436095000	usd
CY2023	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	698000	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-698000	usd
CY2021	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	usd
CY2023	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	36000	usd
CY2022	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	-45000	usd
CY2021	us-gaap	Foreign Currency Transaction Gain Loss Unrealized After Tax ForeignCurrencyTransactionGainLossUnrealizedAfterTax	-12000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-121183000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	184502000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	205875000	usd
CY2023	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	86059000	usd
CY2022	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53938000	usd
CY2021	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53264000	usd
CY2023	fssl	Investment Company Dividend Distribution Increase Decrease InvestmentCompanyDividendDistributionIncreaseDecrease	86059000	usd
CY2022	fssl	Investment Company Dividend Distribution Increase Decrease InvestmentCompanyDividendDistributionIncreaseDecrease	53938000	usd
CY2021	fssl	Investment Company Dividend Distribution Increase Decrease InvestmentCompanyDividendDistributionIncreaseDecrease	53264000	usd
CY2023	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	15549000	usd
CY2022	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	20861000	usd
CY2021	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	21135000	usd
CY2023	fssl	Investment Company Capital Transactions Increase Decrease InvestmentCompanyCapitalTransactionsIncreaseDecrease	15549000	usd
CY2022	fssl	Investment Company Capital Transactions Increase Decrease InvestmentCompanyCapitalTransactionsIncreaseDecrease	20861000	usd
CY2021	fssl	Investment Company Capital Transactions Increase Decrease InvestmentCompanyCapitalTransactionsIncreaseDecrease	21135000	usd
CY2023	us-gaap	Stockholders Equity Period Increase Decrease StockholdersEquityPeriodIncreaseDecrease	-191693000	usd
CY2022	us-gaap	Stockholders Equity Period Increase Decrease StockholdersEquityPeriodIncreaseDecrease	151425000	usd
CY2021	us-gaap	Stockholders Equity Period Increase Decrease StockholdersEquityPeriodIncreaseDecrease	173746000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	1753748000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1602323000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1428577000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	1562055000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	1753748000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1602323000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	-121183000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	184502000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	205875000	usd
CY2023	us-gaap	Payments For Purchase Of Investment Operating Activity PaymentsForPurchaseOfInvestmentOperatingActivity	774503000	usd
CY2022	us-gaap	Payments For Purchase Of Investment Operating Activity PaymentsForPurchaseOfInvestmentOperatingActivity	375192000	usd
CY2021	us-gaap	Payments For Purchase Of Investment Operating Activity PaymentsForPurchaseOfInvestmentOperatingActivity	883097000	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	14199000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	19925000	usd
CY2021	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	27816000	usd
CY2023	us-gaap	Proceeds From Disposition Of Investment Operating Activity ProceedsFromDispositionOfInvestmentOperatingActivity	1135433000	usd
CY2022	us-gaap	Proceeds From Disposition Of Investment Operating Activity ProceedsFromDispositionOfInvestmentOperatingActivity	869402000	usd
CY2021	us-gaap	Proceeds From Disposition Of Investment Operating Activity ProceedsFromDispositionOfInvestmentOperatingActivity	870992000	usd
CY2023	us-gaap	Payments For Purchase Of Securities Operating Activities PaymentsForPurchaseOfSecuritiesOperatingActivities	20994000	usd
CY2022	us-gaap	Payments For Purchase Of Securities Operating Activities PaymentsForPurchaseOfSecuritiesOperatingActivities	0	usd
CY2021	us-gaap	Payments For Purchase Of Securities Operating Activities PaymentsForPurchaseOfSecuritiesOperatingActivities	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-59301000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	37383000	usd
CY2021	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-273439000	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-144904000	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	82009000	usd
CY2021	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	436095000	usd
CY2023	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	698000	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-698000	usd
CY2021	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	usd
CY2023	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	6023000	usd
CY2022	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	6785000	usd
CY2021	us-gaap	Accretion Amortization Of Discounts And Premiums Investments AccretionAmortizationOfDiscountsAndPremiumsInvestments	11170000	usd
CY2023	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	3414000	usd
CY2022	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	6095000	usd
CY2021	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	7824000	usd
CY2023	us-gaap	Increase Decrease In Receivable For Investment Sold IncreaseDecreaseInReceivableForInvestmentSold	20838000	usd
CY2022	us-gaap	Increase Decrease In Receivable For Investment Sold IncreaseDecreaseInReceivableForInvestmentSold	2047000	usd
CY2021	us-gaap	Increase Decrease In Receivable For Investment Sold IncreaseDecreaseInReceivableForInvestmentSold	-2716000	usd
CY2023	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-6839000	usd
CY2022	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-4310000	usd
CY2021	us-gaap	Increase Decrease In Accrued Interest Receivable Net IncreaseDecreaseInAccruedInterestReceivableNet	-463000	usd
CY2023	us-gaap	Increase Decrease In Dividends Receivable IncreaseDecreaseInDividendsReceivable	-518000	usd
CY2022	us-gaap	Increase Decrease In Dividends Receivable IncreaseDecreaseInDividendsReceivable	878000	usd
CY2021	us-gaap	Increase Decrease In Dividends Receivable IncreaseDecreaseInDividendsReceivable	0	usd
CY2023	fssl	Increase Decrease In Derivative Income Receivable IncreaseDecreaseInDerivativeIncomeReceivable	-47000	usd
CY2022	fssl	Increase Decrease In Derivative Income Receivable IncreaseDecreaseInDerivativeIncomeReceivable	83000	usd
CY2023	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	158000	usd
CY2021	us-gaap	Increase Decrease In Payable For Investment Purchased IncreaseDecreaseInPayableForInvestmentPurchased	49500000	usd
CY2022	fssl	Increase Decrease In Derivative Income Payable IncreaseDecreaseInDerivativeIncomePayable	26000	usd
CY2021	fssl	Increase Decrease In Derivative Income Payable IncreaseDecreaseInDerivativeIncomePayable	0	usd
CY2023	us-gaap	Increase Decrease In Management Fee Payable IncreaseDecreaseInManagementFeePayable	-2769000	usd
CY2022	us-gaap	Increase Decrease In Management Fee Payable IncreaseDecreaseInManagementFeePayable	719000	usd
CY2021	us-gaap	Increase Decrease In Management Fee Payable IncreaseDecreaseInManagementFeePayable	310000	usd
CY2023	fssl	Increase Decrease In Administrative Fee Payable IncreaseDecreaseInAdministrativeFeePayable	-978000	usd
CY2022	fssl	Increase Decrease In Administrative Fee Payable IncreaseDecreaseInAdministrativeFeePayable	-238000	usd
CY2021	fssl	Increase Decrease In Administrative Fee Payable IncreaseDecreaseInAdministrativeFeePayable	375000	usd
CY2023	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-11768000	usd
CY2022	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-799000	usd
CY2021	us-gaap	Increase Decrease In Interest Payable Net IncreaseDecreaseInInterestPayableNet	-66000	usd
CY2023	us-gaap	Increase Decrease In Incentive Fee Payable IncreaseDecreaseInIncentiveFeePayable	0	usd
CY2022	us-gaap	Increase Decrease In Incentive Fee Payable IncreaseDecreaseInIncentiveFeePayable	-36000	usd
CY2021	us-gaap	Increase Decrease In Incentive Fee Payable IncreaseDecreaseInIncentiveFeePayable	8000	usd
CY2023	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-1672000	usd
CY2022	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	2815000	usd
CY2021	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	64000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	436502000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	493752000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	53400000	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	56313000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32922000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	31929000	usd
CY2023	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	305676000	usd
CY2022	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	10000000	usd
CY2021	us-gaap	Repayments Of Long Term Lines Of Credit RepaymentsOfLongTermLinesOfCredit	225000000	usd
CY2023	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	457075000	usd
CY2022	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	31925000	usd
CY2021	us-gaap	Repayments Of Senior Debt RepaymentsOfSeniorDebt	0	usd
CY2023	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	6335000	usd
CY2022	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	138000	usd
CY2021	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	128000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-425399000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-45976000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-162057000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	11103000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	447776000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-108657000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	481655000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	33879000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	142536000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	492758000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	481655000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	33879000	usd
CY2023	us-gaap	Stock Issued1 StockIssued1	15549000	usd
CY2022	us-gaap	Stock Issued1 StockIssued1	20861000	usd
CY2021	us-gaap	Stock Issued1 StockIssued1	21135000	usd
CY2023	us-gaap	Transfer To Investments TransferToInvestments	3284000	usd
CY2022	us-gaap	Transfer To Investments TransferToInvestments	1587000	usd
CY2021	us-gaap	Transfer To Investments TransferToInvestments	127399000	usd
CY2023	us-gaap	Transfer Of Investments TransferOfInvestments	3284000	usd
CY2022	us-gaap	Transfer Of Investments TransferOfInvestments	1587000	usd
CY2021	us-gaap	Transfer Of Investments TransferOfInvestments	127399000	usd
CY2023	us-gaap	Income Taxes Paid IncomeTaxesPaid	4081000	usd
CY2022	us-gaap	Income Taxes Paid IncomeTaxesPaid	404000	usd
CY2021	us-gaap	Income Taxes Paid IncomeTaxesPaid	0	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	32052000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	50420000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	46364000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	486059000	usd
CY2023Q4	us-gaap	Restricted Cash RestrictedCash	6699000	usd
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20175000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20033000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20251000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0425
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.030
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.100
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	9975000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	9752000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	9858000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0450
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0550
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	21465000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	18225000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	18222000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0525
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19845000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19937000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19952000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0675
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20915000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20915000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	21098000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0675
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	2688000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	2688000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	2712000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0675
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	1344000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	1344000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1356000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0425
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20000000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19551000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19829000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0418
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19949000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19740000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20061000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.129
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19905000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19620000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19781000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0750
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	17047000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	16855000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	17156000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.078
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.020
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	30673000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	30079000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	30059000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0700
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	14516000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	14326000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	14379000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0400
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19925000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19922000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20008000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0500
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	21000000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20370000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20858000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0500
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19864000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19335000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19106000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0475
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19950000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20070000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20100000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0400
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19893000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19797000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19955000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0900
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.015
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20000000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19400000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19300000	usd
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.020
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19923000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19891000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	19951000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.060
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.095
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.100
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	4015000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	3827000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.100
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0500
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20000000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0350
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19956000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0450
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	9844000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	9868000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	9890000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0450
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0900
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.010
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	23823000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	23823000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23823000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0985
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.018
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	42938000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	42938000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	41882000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0765
CY2023Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	35000000	usd
CY2023Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0750
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.073
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	10601000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	9614000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	10385000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.100
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.083
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20742000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.085
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20000000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	17987000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	17473000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.108
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.063
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	10365000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	28942003	shares
CY2023Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.090
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	19965	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	12493000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	10357000	usd
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.142
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	156250	shares
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.098
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	79336	shares
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	60603000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	43150000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	39427000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1375000	usd
CY2023Q4	fssl	Investment Strike Price InvestmentStrikePrice	1.00
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	35	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	2652000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	3750000	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	6029000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	48400	shares
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	1486929	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	44573000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	105785	shares
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	135062	shares
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	503176	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	93044000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	164040000	usd
CY2023Q4	fssl	Investment Strike Price InvestmentStrikePrice	14.54
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	2187500	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	3083000	usd
CY2023Q4	fssl	Investment Strike Price InvestmentStrikePrice	17.45
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	3125000	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	2623000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	3083000	usd
CY2023Q4	fssl	Investment Strike Price InvestmentStrikePrice	16.27
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	781250	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	576000	usd
CY2023Q4	fssl	Investment Strike Price InvestmentStrikePrice	13.56
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	546880	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	630000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	50	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	7571000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	4418000	usd
CY2023Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	4415749	shares
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20754000	usd
CY2023Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	21000000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20994000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	21000000	usd
CY2023Q4	us-gaap	Investment Owned Percent Of Net Assets InvestmentOwnedPercentOfNetAssets	0.975
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	1543925000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1523196000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	486059000	usd
CY2023Q4	us-gaap	Non Investment Assets Less Non Investment Liabilities Percent Of Net Assets NonInvestmentAssetsLessNonInvestmentLiabilitiesPercentOfNetAssets	-0.286
CY2023Q4	us-gaap	Non Investment Assets Less Non Investment Liabilities NonInvestmentAssetsLessNonInvestmentLiabilities	-447200000	usd
CY2023Q4	us-gaap	Assets Net AssetsNet	1562055000	usd
CY2023Q4	fssl	Qualifying Assets Percent Of Total Assets QualifyingAssetsPercentOfTotalAssets	0.808
CY2023Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.053
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	4767000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	231000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-182000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	675000	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	97000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	3112000	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	3112000	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-3383000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	641000	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	102000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	271000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1885000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	246000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-21704000	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	19573000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	11420000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-10672000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	748000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	41851000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	35240000	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	-11359000	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	4748000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	138000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	8574000	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	256000	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	139000	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	63888000	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23584000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	239000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23823000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	3464000	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	179000	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	11364000	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-307000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	8324000	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-10463000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2023	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2023	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2023	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-21416000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	15566000	usd
CY2023	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2023	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2023	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.030
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.015
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	22734000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20082000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0400
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.030
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.015
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	5359000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	5359000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	5545000	usd
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.080
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.080
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.100
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	39259000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	38085000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	39137000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0900
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	7500000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	6563000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	3713000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0425
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	31575000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	30712000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	31384000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.129
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	100000000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	11081000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0400
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	14286000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	14146000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0375
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	23601000	usd
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	26882000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	26609000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0650
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	81582000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	80371000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	81361000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0750
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	17347000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	17103000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	17406000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0775
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	14648000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	14556000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	14010000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0500
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	7432000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	7305000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	7385000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0500
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	163000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	160000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	162000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0450
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	7920000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	7862000	usd
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0525
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0325
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.005
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	32357000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	32220000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	32026000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0475
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	5760000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	5708000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	5700000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0475
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.070
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.020
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0675
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.060
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.095
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	12121000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	12121000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	9997000	usd
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.100
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	3643000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	3643000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.100
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.010
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	23584000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	23584000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23584000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0785
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.018
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	42500000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	42500000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	41880000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0750
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.015
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20000000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	19848000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20138000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0765
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	39000000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	38440000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	38240000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0625
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.008
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0675
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.015
CY2022Q4	us-gaap	Investment Interest Rate Floor InvestmentInterestRateFloor	0.010
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	20537000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	20537000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	20537000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.063
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.063
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	3098000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.080
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	24299000	usd
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	35118000	usd
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	11693000	usd
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19125000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	18668000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.093
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	29772000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	29633000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	29678000	usd
CY2022Q4	us-gaap	Investment Basis Spread Variable Rate InvestmentBasisSpreadVariableRate	0.0650
CY2022Q4	us-gaap	Investment Owned Balance Principal Amount InvestmentOwnedBalancePrincipalAmount	19500000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.050
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.060
CY2022Q4	us-gaap	Investment Interest Rate Paid In Kind InvestmentInterestRatePaidInKind	0.090
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.142
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.128
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	2640311	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	73114000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	83590000	usd
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.131
CY2022Q4	us-gaap	Investment Interest Rate InvestmentInterestRate	0.098
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	6944444	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	6944000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1219000	usd
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	1.00
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	35	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	2652000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	44700000	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	135062	shares
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	76938973	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	21458000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1885000	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	503176	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	138208000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	312372000	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	1426110	shares
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	14.54
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	2187500	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	3083000	usd
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	17.45
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	3125000	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	2623000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	8000	usd
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	16.27
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	781250	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	576000	usd
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	13.56
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	1968861	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	5000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	11420000	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	9599928	shares
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	50	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	50	shares
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	7571000	usd
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	84779	shares
CY2022Q4	fssl	Investment Strike Price InvestmentStrikePrice	19.59
CY2022Q4	us-gaap	Investment Owned Balance Shares InvestmentOwnedBalanceShares	1586719	shares
CY2022Q4	us-gaap	Investment Owned Percent Of Net Assets InvestmentOwnedPercentOfNetAssets	1.167
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	1922940000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	2047115000	usd
CY2022Q4	us-gaap	Non Investment Assets Less Non Investment Liabilities Percent Of Net Assets NonInvestmentAssetsLessNonInvestmentLiabilitiesPercentOfNetAssets	-0.167
CY2022Q4	us-gaap	Non Investment Assets Less Non Investment Liabilities NonInvestmentAssetsLessNonInvestmentLiabilities	-293367000	usd
CY2022Q4	us-gaap	Assets Net AssetsNet	1753748000	usd
CY2022Q4	fssl	Qualifying Assets Percent Of Total Assets QualifyingAssetsPercentOfTotalAssets	0.775
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	697000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	3674000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	551000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-696000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	4767000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	570000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	105000	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	58055000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	96000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	55096000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	1087000	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-4142000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	2649000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Fee Income FeeIncome	7268000	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	84871000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	54081000	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-9941000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	6681000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-1637000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	6046000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	1795000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-5956000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1885000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	8829000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	4000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	2587000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	11420000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	1726000	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	48356000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	12559000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	173000	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	5881000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	41851000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	3691000	usd
CY2022	us-gaap	Fee Income FeeIncome	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	46339000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	5808000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	11741000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	63888000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	316000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	5808000	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	22745000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	455000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	23200000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	455000	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23688000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	237000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	341000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	23584000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	2620000	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	237000	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2021Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	50770000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	328000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	51098000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	735000	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	10463000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	10463000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	0	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	18060000	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	15899000	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	-2020000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	0	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Additions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossAdditions	0	usd
CY2022	us-gaap	Investments In And Advances To Affiliates At Fair Value Gross Reductions InvestmentsInAndAdvancesToAffiliatesAtFairValueGrossReductions	0	usd
CY2022	us-gaap	Debt And Equity Securities Realized Gain Loss DebtAndEquitySecuritiesRealizedGainLoss	0	usd
CY2022	us-gaap	Debt And Equity Securities Unrealized Gain Loss DebtAndEquitySecuritiesUnrealizedGainLoss	11128000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	36982000	usd
CY2022	us-gaap	Interest Income Operating InterestIncomeOperating	0	usd
CY2022	us-gaap	Interest Income Operating Paid In Kind InterestIncomeOperatingPaidInKind	0	usd
CY2022	us-gaap	Dividend Income Operating DividendIncomeOperating	0	usd
CY2022Q4	us-gaap	Investment Company Financial Commitment To Investee Future Amount InvestmentCompanyFinancialCommitmentToInvesteeFutureAmount	2500000	usd
CY2022Q4	fssl	Investment Company Financial Commitment Fair Value InvestmentCompanyFinancialCommitmentFairValue	2500000	usd
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:6pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Use of Estimates:</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> The preparation of the audited consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Many of the amounts have been rounded, and all amounts are in thousands, except share and per share amounts.</span></div>
CY2021	us-gaap	Fee Income FeeIncome	0	usd
CY2023	fssl	Ordinary Income Percentage OrdinaryIncomePercentage	0.98
CY2023	fssl	Capital Gain Net Income Percentage CapitalGainNetIncomePercentage	0.982
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	0	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1207000	usd
CY2023	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-bottom:6pt;text-indent:36pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Reclassifications:</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> Certain amounts in the consolidated financial statements for the years ended December 31, 2022 and 2021 may have been reclassified to conform to the classifications used to prepare the consolidated financial statements for the year ended December 31, 2023.</span></div>
CY2023	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	4040482	shares
CY2023	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	15549000	usd
CY2022	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	5376174	shares
CY2022	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	20861000	usd
CY2021	us-gaap	Stock Issued During Period Shares Dividend Reinvestment Plan StockIssuedDuringPeriodSharesDividendReinvestmentPlan	6069376	shares
CY2021	us-gaap	Stock Issued During Period Value Dividend Reinvestment Plan StockIssuedDuringPeriodValueDividendReinvestmentPlan	21135000	usd
CY2023	us-gaap	Stock Issued During Period Shares Period Increase Decrease StockIssuedDuringPeriodSharesPeriodIncreaseDecrease	4040482	shares
CY2023	us-gaap	Investment Company Increase Decrease From Share Transaction InvestmentCompanyIncreaseDecreaseFromShareTransaction	15549000	usd
CY2022	us-gaap	Stock Issued During Period Shares Period Increase Decrease StockIssuedDuringPeriodSharesPeriodIncreaseDecrease	5376174	shares
CY2022	us-gaap	Investment Company Increase Decrease From Share Transaction InvestmentCompanyIncreaseDecreaseFromShareTransaction	20861000	usd
CY2021	us-gaap	Stock Issued During Period Shares Period Increase Decrease StockIssuedDuringPeriodSharesPeriodIncreaseDecrease	6069376	shares
CY2021	us-gaap	Investment Company Increase Decrease From Share Transaction InvestmentCompanyIncreaseDecreaseFromShareTransaction	21135000	usd
CY2023Q4	us-gaap	Management Fee Payable ManagementFeePayable	8416000	usd
CY2021	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.1200
CY2021	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53264000	usd
CY2022	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.1200
CY2022	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53938000	usd
CY2023	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.1892
CY2023	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	86059000	usd
CY2023Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.0683
CY2023Q4	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.0643
CY2023Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.0609
CY2023	fssl	Investment Company Annualized Distribution Rate InvestmentCompanyAnnualizedDistributionRate	0.075
CY2023Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.43
CY2023	fssl	Investment Company Annualized Distribution Rate Maximum Cap InvestmentCompanyAnnualizedDistributionRateMaximumCap	0.150
CY2023	us-gaap	Investment Company Distribution Ordinary Income InvestmentCompanyDistributionOrdinaryIncome	86059000	usd
CY2023	fssl	Investment Company Distribution Ordinary Income Percent Of Total Distributions InvestmentCompanyDistributionOrdinaryIncomePercentOfTotalDistributions	1
CY2022	us-gaap	Investment Company Distribution Ordinary Income InvestmentCompanyDistributionOrdinaryIncome	53938000	usd
CY2022	fssl	Investment Company Distribution Ordinary Income Percent Of Total Distributions InvestmentCompanyDistributionOrdinaryIncomePercentOfTotalDistributions	1
CY2021	us-gaap	Investment Company Distribution Ordinary Income InvestmentCompanyDistributionOrdinaryIncome	53264000	usd
CY2021	fssl	Investment Company Distribution Ordinary Income Percent Of Total Distributions InvestmentCompanyDistributionOrdinaryIncomePercentOfTotalDistributions	1
CY2023	fssl	Investment Company Distribution Short Term Capital Gain InvestmentCompanyDistributionShortTermCapitalGain	0	usd
CY2023	fssl	Investment Company Distribution Short Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionShortTermCapitalGainPercentOfTotalDistributions	0
CY2022	fssl	Investment Company Distribution Short Term Capital Gain InvestmentCompanyDistributionShortTermCapitalGain	0	usd
CY2022	fssl	Investment Company Distribution Short Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionShortTermCapitalGainPercentOfTotalDistributions	0
CY2021	fssl	Investment Company Distribution Short Term Capital Gain InvestmentCompanyDistributionShortTermCapitalGain	0	usd
CY2021	fssl	Investment Company Distribution Short Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionShortTermCapitalGainPercentOfTotalDistributions	0
CY2023	us-gaap	Investment Company Distribution Long Term Capital Gain InvestmentCompanyDistributionLongTermCapitalGain	0	usd
CY2023	fssl	Investment Company Distribution Long Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionLongTermCapitalGainPercentOfTotalDistributions	0
CY2022	us-gaap	Investment Company Distribution Long Term Capital Gain InvestmentCompanyDistributionLongTermCapitalGain	0	usd
CY2022	fssl	Investment Company Distribution Long Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionLongTermCapitalGainPercentOfTotalDistributions	0
CY2021	us-gaap	Investment Company Distribution Long Term Capital Gain InvestmentCompanyDistributionLongTermCapitalGain	0	usd
CY2021	fssl	Investment Company Distribution Long Term Capital Gain Percent Of Total Distributions InvestmentCompanyDistributionLongTermCapitalGainPercentOfTotalDistributions	0
CY2023	us-gaap	Investment Company Tax Return Of Capital Distribution InvestmentCompanyTaxReturnOfCapitalDistribution	0	usd
CY2023	fssl	Investment Company Tax Return Of Capital Distribution Percent Of Total Distributions InvestmentCompanyTaxReturnOfCapitalDistributionPercentOfTotalDistributions	0
CY2022	us-gaap	Investment Company Tax Return Of Capital Distribution InvestmentCompanyTaxReturnOfCapitalDistribution	0	usd
CY2022	fssl	Investment Company Tax Return Of Capital Distribution Percent Of Total Distributions InvestmentCompanyTaxReturnOfCapitalDistributionPercentOfTotalDistributions	0
CY2021	us-gaap	Investment Company Tax Return Of Capital Distribution InvestmentCompanyTaxReturnOfCapitalDistribution	0	usd
CY2021	fssl	Investment Company Tax Return Of Capital Distribution Percent Of Total Distributions InvestmentCompanyTaxReturnOfCapitalDistributionPercentOfTotalDistributions	0
CY2023	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	86059000	usd
CY2023	fssl	Investment Company Dividend Distribution Percent Of Total Distributions InvestmentCompanyDividendDistributionPercentOfTotalDistributions	1
CY2022	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53938000	usd
CY2022	fssl	Investment Company Dividend Distribution Percent Of Total Distributions InvestmentCompanyDividendDistributionPercentOfTotalDistributions	1
CY2021	us-gaap	Investment Company Dividend Distribution InvestmentCompanyDividendDistribution	53264000	usd
CY2021	fssl	Investment Company Dividend Distribution Percent Of Total Distributions InvestmentCompanyDividendDistributionPercentOfTotalDistributions	1
CY2023	fssl	Gross Investment Income Percentage Attributable To Cash Income Earned GrossInvestmentIncomePercentageAttributableToCashIncomeEarned	0.871
CY2022	fssl	Gross Investment Income Percentage Attributable To Cash Income Earned GrossInvestmentIncomePercentageAttributableToCashIncomeEarned	0.855
CY2021	fssl	Gross Investment Income Percentage Attributable To Cash Income Earned GrossInvestmentIncomePercentageAttributableToCashIncomeEarned	0.741
CY2023	fssl	Gross Investment Income Percentage Attributable To Paid In Kind Interest GrossInvestmentIncomePercentageAttributableToPaidInKindInterest	0.090
CY2022	fssl	Gross Investment Income Percentage Attributable To Paid In Kind Interest GrossInvestmentIncomePercentageAttributableToPaidInKindInterest	0.108
CY2021	fssl	Gross Investment Income Percentage Attributable To Paid In Kind Interest GrossInvestmentIncomePercentageAttributableToPaidInKindInterest	0.185
CY2023	fssl	Gross Investment Income Percentage Attributable To Non Cash Accretion Of Discount GrossInvestmentIncomePercentageAttributableToNonCashAccretionOfDiscount	0.039
CY2022	fssl	Gross Investment Income Percentage Attributable To Non Cash Accretion Of Discount GrossInvestmentIncomePercentageAttributableToNonCashAccretionOfDiscount	0.037
CY2021	fssl	Gross Investment Income Percentage Attributable To Non Cash Accretion Of Discount GrossInvestmentIncomePercentageAttributableToNonCashAccretionOfDiscount	0.074
CY2023	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	101804000	usd
CY2022	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	69711000	usd
CY2021	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	80892000	usd
CY2023Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Ordinary Income Loss InvestmentCompanyDistributableEarningsLossAccumulatedOrdinaryIncomeLoss	36369000	usd
CY2022Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Ordinary Income Loss InvestmentCompanyDistributableEarningsLossAccumulatedOrdinaryIncomeLoss	21803000	usd
CY2023Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Long Term Capital Gain Loss InvestmentCompanyDistributableEarningsLossAccumulatedLongTermCapitalGainLoss	1521281000	usd
CY2023	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	81363000	usd
CY2022	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	69769000	usd
CY2021	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	43259000	usd
CY2023	fssl	Investment Tax Basis Reconciliation Deferred Debt Issuance Cost Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationDeferredDebtIssuanceCostIncreaseDecreaseInTaxableIncome	-5072000	usd
CY2022	fssl	Investment Tax Basis Reconciliation Deferred Debt Issuance Cost Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationDeferredDebtIssuanceCostIncreaseDecreaseInTaxableIncome	-12480000	usd
CY2021	fssl	Investment Tax Basis Reconciliation Deferred Debt Issuance Cost Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationDeferredDebtIssuanceCostIncreaseDecreaseInTaxableIncome	-4030000	usd
CY2023	fssl	Investment Tax Basis Reconciliation Consolidation Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationConsolidationIncreaseDecreaseInTaxableIncome	2652000	usd
CY2022	fssl	Investment Tax Basis Reconciliation Consolidation Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationConsolidationIncreaseDecreaseInTaxableIncome	1242000	usd
CY2021	fssl	Investment Tax Basis Reconciliation Consolidation Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationConsolidationIncreaseDecreaseInTaxableIncome	13532000	usd
CY2023	fssl	Investment Tax Basis Reconciliation Other Taxable Income Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherTaxableIncomeIncreaseDecreaseInTaxableIncome	22612000	usd
CY2022	fssl	Investment Tax Basis Reconciliation Other Taxable Income Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherTaxableIncomeIncreaseDecreaseInTaxableIncome	13036000	usd
CY2021	fssl	Investment Tax Basis Reconciliation Other Taxable Income Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherTaxableIncomeIncreaseDecreaseInTaxableIncome	28182000	usd
CY2023	fssl	Investment Tax Basis Reconciliation Other Deductions Or Losses Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherDeductionsOrLossesIncreaseDecreaseInTaxableIncome	249000	usd
CY2022	fssl	Investment Tax Basis Reconciliation Other Deductions Or Losses Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherDeductionsOrLossesIncreaseDecreaseInTaxableIncome	-1856000	usd
CY2021	fssl	Investment Tax Basis Reconciliation Other Deductions Or Losses Increase Decrease In Taxable Income InvestmentTaxBasisReconciliationOtherDeductionsOrLossesIncreaseDecreaseInTaxableIncome	-51000	usd
CY2023	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	101804000	usd
CY2022	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	69711000	usd
CY2021	fssl	Investment Company Distributable Earnings Loss Before Deductions InvestmentCompanyDistributableEarningsLossBeforeDeductions	80892000	usd
CY2023	us-gaap	Investment Company Tax Reclassification Increase Decrease InvestmentCompanyTaxReclassificationIncreaseDecrease	-21053000	usd
CY2022	us-gaap	Investment Company Tax Reclassification Increase Decrease InvestmentCompanyTaxReclassificationIncreaseDecrease	41185000	usd
CY2023Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Ordinary Income Loss InvestmentCompanyDistributableEarningsLossAccumulatedOrdinaryIncomeLoss	36369000	usd
CY2022Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Ordinary Income Loss InvestmentCompanyDistributableEarningsLossAccumulatedOrdinaryIncomeLoss	21803000	usd
CY2023Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Capital Loss Carryforward InvestmentCompanyDistributableEarningsLossAccumulatedCapitalLossCarryforward	1595362000	usd
CY2022Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Capital Loss Carryforward InvestmentCompanyDistributableEarningsLossAccumulatedCapitalLossCarryforward	1282145000	usd
CY2023Q4	fssl	Investment Company Distributable Earnings Loss Accumulated Other Temporary Differences InvestmentCompanyDistributableEarningsLossAccumulatedOtherTemporaryDifferences	-670000	usd
CY2022Q4	fssl	Investment Company Distributable Earnings Loss Accumulated Other Temporary Differences InvestmentCompanyDistributableEarningsLossAccumulatedOtherTemporaryDifferences	-83000	usd
CY2023Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Appreciation Depreciation InvestmentCompanyDistributableEarningsLossAccumulatedAppreciationDepreciation	-64522000	usd
CY2022Q4	us-gaap	Investment Company Distributable Earnings Loss Accumulated Appreciation Depreciation InvestmentCompanyDistributableEarningsLossAccumulatedAppreciationDepreciation	-177571000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1624185000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	-1437996000	usd
CY2023Q4	fssl	Investment Company Distributable Earnings Loss Accumulated Short Term Capital Gain Loss InvestmentCompanyDistributableEarningsLossAccumulatedShortTermCapitalGainLoss	74081000	usd
CY2023Q4	us-gaap	Tax Basis Of Investments Gross Unrealized Appreciation TaxBasisOfInvestmentsGrossUnrealizedAppreciation	148817000	usd
CY2022Q4	us-gaap	Tax Basis Of Investments Gross Unrealized Appreciation TaxBasisOfInvestmentsGrossUnrealizedAppreciation	334635000	usd
CY2023Q4	us-gaap	Tax Basis Of Investments Gross Unrealized Depreciation TaxBasisOfInvestmentsGrossUnrealizedDepreciation	213339000	usd
CY2022Q4	us-gaap	Tax Basis Of Investments Gross Unrealized Depreciation TaxBasisOfInvestmentsGrossUnrealizedDepreciation	512206000	usd
CY2023Q4	us-gaap	Tax Basis Of Investments Cost For Income Tax Purposes TaxBasisOfInvestmentsCostForIncomeTaxPurposes	1587709000	usd
CY2022Q4	us-gaap	Tax Basis Of Investments Cost For Income Tax Purposes TaxBasisOfInvestmentsCostForIncomeTaxPurposes	2223943000	usd
CY2023Q4	us-gaap	Tax Basis Of Investments Unrealized Appreciation Depreciation Net TaxBasisOfInvestmentsUnrealizedAppreciationDepreciationNet	-64513000	usd
CY2022Q4	us-gaap	Tax Basis Of Investments Unrealized Appreciation Depreciation Net TaxBasisOfInvestmentsUnrealizedAppreciationDepreciationNet	-176828000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	142608000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Investments DeferredTaxAssetsInvestments	145383000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	2595000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Investments DeferredTaxLiabilitiesInvestments	28753000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	140013000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	116630000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	1207000	usd
CY2023Q4	us-gaap	Derivative Assets DerivativeAssets	0	usd
CY2023Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	0	usd
CY2022Q4	us-gaap	Derivative Assets DerivativeAssets	0	usd
CY2022Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	698000	usd
CY2023	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	1048000	usd
CY2022	us-gaap	Gain Loss On Sale Of Derivatives GainLossOnSaleOfDerivatives	-2785000	usd
CY2023	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	698000	usd
CY2022	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-698000	usd
CY2023Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	1543925000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1523196000	usd
CY2022Q4	us-gaap	Investment Owned At Cost InvestmentOwnedAtCost	1922940000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	2047115000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1523196000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	2047115000	usd
CY2023Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	1523196000	usd
CY2022Q4	us-gaap	Investment Owned At Fair Value InvestmentOwnedAtFairValue	2047115000	usd
CY2023Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	0	usd
CY2023Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	0	usd
CY2022Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	0	usd
CY2022Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	698000	usd
CY2022Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.88
CY2021Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.59
CY2020Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.25
CY2019Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	5.43
CY2018Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	6.01
CY2023	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.18
CY2022	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.16
CY2021	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.09
CY2020	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.19
CY2019	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.46
CY2023	us-gaap	Investment Company Gain Loss On Investment Per Share InvestmentCompanyGainLossOnInvestmentPerShare	-0.44
CY2022	us-gaap	Investment Company Gain Loss On Investment Per Share InvestmentCompanyGainLossOnInvestmentPerShare	0.25
CY2021	us-gaap	Investment Company Gain Loss On Investment Per Share InvestmentCompanyGainLossOnInvestmentPerShare	0.37
CY2020	us-gaap	Investment Company Gain Loss On Investment Per Share InvestmentCompanyGainLossOnInvestmentPerShare	-2.20
CY2019	us-gaap	Investment Company Gain Loss On Investment Per Share InvestmentCompanyGainLossOnInvestmentPerShare	-0.54
CY2023	us-gaap	Investment Company Investment Income Loss From Operations Per Share InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare	-0.26
CY2022	us-gaap	Investment Company Investment Income Loss From Operations Per Share InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare	0.41
CY2021	us-gaap	Investment Company Investment Income Loss From Operations Per Share InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare	0.46
CY2020	us-gaap	Investment Company Investment Income Loss From Operations Per Share InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare	-2.01
CY2019	us-gaap	Investment Company Investment Income Loss From Operations Per Share InvestmentCompanyInvestmentIncomeLossFromOperationsPerShare	-0.08
CY2023	fssl	Investment Company Distribution To Shareholder From Net Investment Income InvestmentCompanyDistributionToShareholderFromNetInvestmentIncome	0.19
CY2022	fssl	Investment Company Distribution To Shareholder From Net Investment Income InvestmentCompanyDistributionToShareholderFromNetInvestmentIncome	0.12
CY2021	fssl	Investment Company Distribution To Shareholder From Net Investment Income InvestmentCompanyDistributionToShareholderFromNetInvestmentIncome	0.12
CY2020	fssl	Investment Company Distribution To Shareholder From Net Investment Income InvestmentCompanyDistributionToShareholderFromNetInvestmentIncome	0.14
CY2019	fssl	Investment Company Distribution To Shareholder From Net Investment Income InvestmentCompanyDistributionToShareholderFromNetInvestmentIncome	0.50
CY2023	us-gaap	Investment Company Tax Return Of Capital Distribution Per Share InvestmentCompanyTaxReturnOfCapitalDistributionPerShare	0
CY2022	us-gaap	Investment Company Tax Return Of Capital Distribution Per Share InvestmentCompanyTaxReturnOfCapitalDistributionPerShare	0
CY2021	us-gaap	Investment Company Tax Return Of Capital Distribution Per Share InvestmentCompanyTaxReturnOfCapitalDistributionPerShare	0
CY2020	us-gaap	Investment Company Tax Return Of Capital Distribution Per Share InvestmentCompanyTaxReturnOfCapitalDistributionPerShare	0.03
CY2019	us-gaap	Investment Company Tax Return Of Capital Distribution Per Share InvestmentCompanyTaxReturnOfCapitalDistributionPerShare	0
CY2023	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.19
CY2022	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.12
CY2021	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.12
CY2020	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.17
CY2019	us-gaap	Investment Company Distribution To Shareholders Per Share InvestmentCompanyDistributionToShareholdersPerShare	0.50
CY2023	us-gaap	Investment Company Issuance Of Shares Per Share InvestmentCompanyIssuanceOfSharesPerShare	0
CY2022	us-gaap	Investment Company Issuance Of Shares Per Share InvestmentCompanyIssuanceOfSharesPerShare	0
CY2021	us-gaap	Investment Company Issuance Of Shares Per Share InvestmentCompanyIssuanceOfSharesPerShare	0
CY2020	us-gaap	Investment Company Issuance Of Shares Per Share InvestmentCompanyIssuanceOfSharesPerShare	0
CY2019	us-gaap	Investment Company Issuance Of Shares Per Share InvestmentCompanyIssuanceOfSharesPerShare	0
CY2023	fssl	Investment Company Capital Share Transaction Per Share InvestmentCompanyCapitalShareTransactionPerShare	0
CY2022	fssl	Investment Company Capital Share Transaction Per Share InvestmentCompanyCapitalShareTransactionPerShare	0
CY2021	fssl	Investment Company Capital Share Transaction Per Share InvestmentCompanyCapitalShareTransactionPerShare	0
CY2020	fssl	Investment Company Capital Share Transaction Per Share InvestmentCompanyCapitalShareTransactionPerShare	0
CY2019	fssl	Investment Company Capital Share Transaction Per Share InvestmentCompanyCapitalShareTransactionPerShare	0
CY2023Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.43
CY2022Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.88
CY2021Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.59
CY2020Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	3.25
CY2019Q4	us-gaap	Net Asset Value Per Share NetAssetValuePerShare	5.43
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	455506155	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	451465673	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	446089499	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	440020123	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	438477007	shares
CY2023	us-gaap	Investment Company Total Return InvestmentCompanyTotalReturn	-0.0689
CY2022	us-gaap	Investment Company Total Return InvestmentCompanyTotalReturn	0.1139
CY2021	us-gaap	Investment Company Total Return InvestmentCompanyTotalReturn	0.1422
CY2020	us-gaap	Investment Company Total Return InvestmentCompanyTotalReturn	-0.3768
CY2019	us-gaap	Investment Company Total Return InvestmentCompanyTotalReturn	-0.0183
CY2023	fssl	Investment Company Total Return Without Assuming Reinvestment Of Distributions InvestmentCompanyTotalReturnWithoutAssumingReinvestmentOfDistributions	-0.0670
CY2022	fssl	Investment Company Total Return Without Assuming Reinvestment Of Distributions InvestmentCompanyTotalReturnWithoutAssumingReinvestmentOfDistributions	0.1129
CY2021	fssl	Investment Company Total Return Without Assuming Reinvestment Of Distributions InvestmentCompanyTotalReturnWithoutAssumingReinvestmentOfDistributions	0.1415
CY2020	fssl	Investment Company Total Return Without Assuming Reinvestment Of Distributions InvestmentCompanyTotalReturnWithoutAssumingReinvestmentOfDistributions	-0.3702
CY2019	fssl	Investment Company Total Return Without Assuming Reinvestment Of Distributions InvestmentCompanyTotalReturnWithoutAssumingReinvestmentOfDistributions	-0.0133
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	1562055000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	1753748000	usd
CY2021Q4	us-gaap	Stockholders Equity StockholdersEquity	1602323000	usd
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	1428577000	usd
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	2379605000	usd
CY2023	us-gaap	Investment Company Investment Income Loss Ratio InvestmentCompanyInvestmentIncomeLossRatio	0.0477
CY2022	us-gaap	Investment Company Investment Income Loss Ratio InvestmentCompanyInvestmentIncomeLossRatio	0.0402
CY2021	us-gaap	Investment Company Investment Income Loss Ratio InvestmentCompanyInvestmentIncomeLossRatio	0.0277
CY2020	us-gaap	Investment Company Investment Income Loss Ratio InvestmentCompanyInvestmentIncomeLossRatio	0.0482
CY2019	us-gaap	Investment Company Investment Income Loss Ratio InvestmentCompanyInvestmentIncomeLossRatio	0.0776
CY2023	us-gaap	Investment Company Expense Ratio Including Incentive Fee InvestmentCompanyExpenseRatioIncludingIncentiveFee	0.0450
CY2022	us-gaap	Investment Company Expense Ratio Including Incentive Fee InvestmentCompanyExpenseRatioIncludingIncentiveFee	0.0678
CY2021	us-gaap	Investment Company Expense Ratio Including Incentive Fee InvestmentCompanyExpenseRatioIncludingIncentiveFee	0.0696
CY2020	us-gaap	Investment Company Expense Ratio Including Incentive Fee InvestmentCompanyExpenseRatioIncludingIncentiveFee	0.0820
CY2019	us-gaap	Investment Company Expense Ratio Including Incentive Fee InvestmentCompanyExpenseRatioIncludingIncentiveFee	0.0654
CY2023	fssl	Investment Company Expense Ratio Management Fee Waiver InvestmentCompanyExpenseRatioManagementFeeWaiver	0.0002
CY2022	fssl	Investment Company Expense Ratio Management Fee Waiver InvestmentCompanyExpenseRatioManagementFeeWaiver	0.0015
CY2021	fssl	Investment Company Expense Ratio Management Fee Waiver InvestmentCompanyExpenseRatioManagementFeeWaiver	0.0009
CY2020	fssl	Investment Company Expense Ratio Management Fee Waiver InvestmentCompanyExpenseRatioManagementFeeWaiver	0.0004
CY2019	fssl	Investment Company Expense Ratio Management Fee Waiver InvestmentCompanyExpenseRatioManagementFeeWaiver	0.0023
CY2023	fssl	Investment Company Expense Ratio Including Fee Waiver And Reimbursements InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements	0.0448
CY2022	fssl	Investment Company Expense Ratio Including Fee Waiver And Reimbursements InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements	0.0663
CY2021	fssl	Investment Company Expense Ratio Including Fee Waiver And Reimbursements InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements	0.0687
CY2020	fssl	Investment Company Expense Ratio Including Fee Waiver And Reimbursements InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements	0.0816
CY2019	fssl	Investment Company Expense Ratio Including Fee Waiver And Reimbursements InvestmentCompanyExpenseRatioIncludingFeeWaiverAndReimbursements	0.0631
CY2023	fssl	Investment Company Interest Expense To Average Net Assets InvestmentCompanyInterestExpenseToAverageNetAssets	0.0139
CY2022	fssl	Investment Company Interest Expense To Average Net Assets InvestmentCompanyInterestExpenseToAverageNetAssets	0.0321
CY2021	fssl	Investment Company Interest Expense To Average Net Assets InvestmentCompanyInterestExpenseToAverageNetAssets	0.0346
CY2020	fssl	Investment Company Interest Expense To Average Net Assets InvestmentCompanyInterestExpenseToAverageNetAssets	0.0439
CY2019	fssl	Investment Company Interest Expense To Average Net Assets InvestmentCompanyInterestExpenseToAverageNetAssets	0.0340
CY2023	fssl	Investment Company Federal And State Taxes To Average Net Assets InvestmentCompanyFederalAndStateTaxesToAverageNetAssets	0.0015
CY2022	fssl	Investment Company Federal And State Taxes To Average Net Assets InvestmentCompanyFederalAndStateTaxesToAverageNetAssets	0.0013
CY2021	fssl	Investment Company Federal And State Taxes To Average Net Assets InvestmentCompanyFederalAndStateTaxesToAverageNetAssets	0
CY2020	fssl	Investment Company Federal And State Taxes To Average Net Assets InvestmentCompanyFederalAndStateTaxesToAverageNetAssets	0
CY2019	fssl	Investment Company Federal And State Taxes To Average Net Assets InvestmentCompanyFederalAndStateTaxesToAverageNetAssets	0
CY2023	us-gaap	Investment Company Portfolio Turnover InvestmentCompanyPortfolioTurnover	0.4584
CY2022	us-gaap	Investment Company Portfolio Turnover InvestmentCompanyPortfolioTurnover	0.1615
CY2021	us-gaap	Investment Company Portfolio Turnover InvestmentCompanyPortfolioTurnover	0.4425
CY2020	us-gaap	Investment Company Portfolio Turnover InvestmentCompanyPortfolioTurnover	0.2654
CY2019	us-gaap	Investment Company Portfolio Turnover InvestmentCompanyPortfolioTurnover	0.3288
CY2023Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	400000000	usd
CY2022Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	762751000	usd
CY2021Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	775667000	usd
CY2020Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	905667000	usd
CY2019Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	1236667000	usd
CY2023Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	4905
CY2022Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	3299
CY2022Q2	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	20836000	usd
CY2021Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	3066
CY2020Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	2577
CY2019Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	2924
CY2023Q4	us-gaap	Investment Company Senior Security Indebtedness Asset Coverage Ratio InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatio	4.91
CY2022Q4	us-gaap	Investment Company Senior Security Indebtedness Asset Coverage Ratio InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatio	3.30
CY2021Q4	us-gaap	Investment Company Senior Security Indebtedness Asset Coverage Ratio InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatio	3.07
CY2020Q4	us-gaap	Investment Company Senior Security Indebtedness Asset Coverage Ratio InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatio	2.58
CY2019Q4	us-gaap	Investment Company Senior Security Indebtedness Asset Coverage Ratio InvestmentCompanySeniorSecurityIndebtednessAssetCoverageRatio	2.92
CY2023	fssl	Investment Company Investment Income Loss Ratio Excluding Advisors Agreement To Offset Management Fee InvestmentCompanyInvestmentIncomeLossRatioExcludingAdvisorsAgreementToOffsetManagementFee	0.0475
CY2022	fssl	Investment Company Investment Income Loss Ratio Excluding Advisors Agreement To Offset Management Fee InvestmentCompanyInvestmentIncomeLossRatioExcludingAdvisorsAgreementToOffsetManagementFee	0.0387
CY2021	fssl	Investment Company Investment Income Loss Ratio Excluding Advisors Agreement To Offset Management Fee InvestmentCompanyInvestmentIncomeLossRatioExcludingAdvisorsAgreementToOffsetManagementFee	0.0268
CY2020	fssl	Investment Company Investment Income Loss Ratio Excluding Advisors Agreement To Offset Management Fee InvestmentCompanyInvestmentIncomeLossRatioExcludingAdvisorsAgreementToOffsetManagementFee	0.0478
CY2019	fssl	Investment Company Investment Income Loss Ratio Excluding Advisors Agreement To Offset Management Fee InvestmentCompanyInvestmentIncomeLossRatioExcludingAdvisorsAgreementToOffsetManagementFee	0.0753
CY2023Q4	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	42708000	usd
CY2023Q3	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	30443000	usd
CY2023Q2	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	41476000	usd
CY2023Q1	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	43095000	usd
CY2023Q4	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	17125000	usd
CY2023Q3	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	13788000	usd
CY2023Q2	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	19594000	usd
CY2023Q1	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	26193000	usd
CY2023Q4	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	4000	usd
CY2023Q3	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	63000	usd
CY2023Q2	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	19000	usd
CY2023Q1	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	255000	usd
CY2023Q4	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	17121000	usd
CY2023Q3	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	13725000	usd
CY2023Q2	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	19575000	usd
CY2023Q1	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	25938000	usd
CY2023Q4	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	25587000	usd
CY2023Q3	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	16718000	usd
CY2023Q2	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	21901000	usd
CY2023Q1	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	17157000	usd
CY2023Q4	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-62142000	usd
CY2023Q3	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-44141000	usd
CY2023Q2	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-46552000	usd
CY2023Q1	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-49711000	usd
CY2023Q4	us-gaap	Net Income Loss NetIncomeLoss	-36555000	usd
CY2023Q3	us-gaap	Net Income Loss NetIncomeLoss	-27423000	usd
CY2023Q2	us-gaap	Net Income Loss NetIncomeLoss	-24651000	usd
CY2023Q1	us-gaap	Net Income Loss NetIncomeLoss	-32554000	usd
CY2023Q4	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.05
CY2023Q3	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.04
CY2023Q2	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.05
CY2023Q1	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.04
CY2023Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.08
CY2023Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.08
CY2023Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.06
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.06
CY2023Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.05
CY2023Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.05
CY2023Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.07
CY2023Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.07
CY2023Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	455506174	shares
CY2023Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	455506174	shares
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	455401486	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	455401486	shares
CY2023Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	454041028	shares
CY2023Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	454041028	shares
CY2023Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	452684238	shares
CY2023Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	452684238	shares
CY2022Q4	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	59535000	usd
CY2022Q3	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	42450000	usd
CY2022Q2	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	47073000	usd
CY2022Q1	us-gaap	Gross Investment Income Operating GrossInvestmentIncomeOperating	35909000	usd
CY2022Q4	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	32157000	usd
CY2022Q3	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	29306000	usd
CY2022Q2	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	27937000	usd
CY2022Q1	fssl	Investment Company Total Expenses And Federal Income And Excise Taxes InvestmentCompanyTotalExpensesAndFederalIncomeAndExciseTaxes	28417000	usd
CY2022Q4	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	13000	usd
CY2022Q3	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	208000	usd
CY2022Q2	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	1700000	usd
CY2022Q1	fssl	Investment Company Management Fee Offset InvestmentCompanyManagementFeeOffset	698000	usd
CY2022Q4	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	32144000	usd
CY2022Q3	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	29098000	usd
CY2022Q2	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	26237000	usd
CY2022Q1	fssl	Investment Company Net Expenses And Federal Income And Excise Taxes InvestmentCompanyNetExpensesAndFederalIncomeAndExciseTaxes	27719000	usd
CY2022Q4	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	27391000	usd
CY2022Q3	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	13352000	usd
CY2023Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	400000000	usd
CY2023Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	100000000	usd
CY2022Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	762751000	usd
CY2022Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	0	usd
CY2023	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	20284000	usd
CY2023	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	3414000	usd
CY2023	us-gaap	Interest Expense Debt InterestExpenseDebt	23698000	usd
CY2022	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	49621000	usd
CY2022	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	6095000	usd
CY2022	us-gaap	Interest Expense Debt InterestExpenseDebt	55716000	usd
CY2021	us-gaap	Interest Expense Debt Excluding Amortization InterestExpenseDebtExcludingAmortization	46298000	usd
CY2021	us-gaap	Amortization Of Debt Discount Premium AmortizationOfDebtDiscountPremium	7824000	usd
CY2021	us-gaap	Interest Expense Debt InterestExpenseDebt	54122000	usd
	us-gaap	Long Term Debt Average Amount Outstanding LongTermDebtAverageAmountOutstanding	557446000	usd
CY2023Q2	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0749
CY2022	us-gaap	Long Term Debt Average Amount Outstanding LongTermDebtAverageAmountOutstanding	768752000	usd
CY2022Q4	us-gaap	Debt Weighted Average Interest Rate DebtWeightedAverageInterestRate	0.0725
CY2022Q4	us-gaap	Debt Instrument Interest Rate Effective Percentage DebtInstrumentInterestRateEffectivePercentage	0.0747
CY2023Q3	fssl	Number Of Special Purpose Financing Subsidiaries NumberOfSpecialPurposeFinancingSubsidiaries	2	subsidiary
CY2019Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	1236667000	usd
CY2019Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	2924
CY2020Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	905667000	usd
CY2020Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	2577
CY2021Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	775667000	usd
CY2021Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	3066
CY2022Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	762751000	usd
CY2022Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	3299
CY2023Q4	cef	Senior Securities Amt SeniorSecuritiesAmt	400000000	usd
CY2023Q4	cef	Senior Securities Cvg Per Unit SeniorSecuritiesCvgPerUnit	4905
CY2022Q1	us-gaap	Investment Income Operating After Expense And Tax InvestmentIncomeOperatingAfterExpenseAndTax	8190000	usd
CY2022Q4	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	2849000	usd
CY2022Q3	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-64453000	usd
CY2022Q2	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	-5256000	usd
CY2022Q1	us-gaap	Realized And Unrealized Gain Loss Investment Derivative And Foreign Currency Transaction Operating After Tax RealizedAndUnrealizedGainLossInvestmentDerivativeAndForeignCurrencyTransactionOperatingAfterTax	181593000	usd
CY2022Q4	us-gaap	Net Income Loss NetIncomeLoss	30240000	usd
CY2022Q3	us-gaap	Net Income Loss NetIncomeLoss	-51101000	usd
CY2022Q2	us-gaap	Net Income Loss NetIncomeLoss	15580000	usd
CY2022Q1	us-gaap	Net Income Loss NetIncomeLoss	189783000	usd
CY2022Q4	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.06
CY2022Q3	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.03
CY2022Q2	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.05
CY2022Q1	us-gaap	Investment Company Investment Income Loss Per Share InvestmentCompanyInvestmentIncomeLossPerShare	0.02
CY2022Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.07
CY2022Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.07
CY2022Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.11
CY2022Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.11
CY2022Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.03
CY2022Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.03
CY2022Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.42
CY2022Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.42
CY2022Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	451364025	shares
CY2022Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	451364025	shares
CY2022Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	450023829	shares
CY2022Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	450023829	shares
CY2022Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	448730149	shares
CY2022Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	448730149	shares
CY2022Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	447404395	shares
CY2022Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	447404395	shares
CY2023	fssl	Investment Company Percentage Of Distributions Qualified As Excess Interest Income InvestmentCompanyPercentageOfDistributionsQualifiedAsExcessInterestIncome	0.933
CY2023Q4	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2023Q4	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false

Files In Submission

Name	View Source	Status
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0001628280-24-011529-index.html	Edgar Link	pending
0001628280-24-011529.txt	Edgar Link	pending
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2024 Q1 Form 10-K Financial Statement

#000162828024011529 Filed on March 15, 2024

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$FSEN FS Specialty Lending Fund Stock $fsen

2024 Q1 Form 10-K Financial Statement

#000162828024011529 Filed on March 15, 2024

Income Statement

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