v3.25.3

Fair Value - Fair Value - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 95,000	$ 107,600
Level 3 [Member] | Common Equity/Equity Interests/Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	284,000
Recurring Fair Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	2,105,293	2,005,634
Recurring Fair Value [Member] | Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	48,360	49,091
Recurring Fair Value [Member] | Senior Secured Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	1,251,236	1,117,118
Recurring Fair Value [Member] | Senior Secured Loans [Member] | Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Equipment Financing [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	121,823	181,016
Recurring Fair Value [Member] | Equipment Financing [Member] | Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Preferred Equity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	32,156	31,682
Recurring Fair Value [Member] | Preferred Equity [Member] | Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Common Equity/Equity Interests/Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	700,078	675,818
Recurring Fair Value [Member] | Common Equity/Equity Interests/Warrants [Member] | Measured at Net Asset Value [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	48,360	49,091
Recurring Fair Value [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	216	257
Recurring Fair Value [Member] | Level 1 [Member] | Senior Secured Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 1 [Member] | Equipment Financing [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 1 [Member] | Preferred Equity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 1 [Member] | Common Equity/Equity Interests/Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	216	257
Recurring Fair Value [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 2 [Member] | Senior Secured Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 2 [Member] | Equipment Financing [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 2 [Member] | Preferred Equity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 2 [Member] | Common Equity/Equity Interests/Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	0	0
Recurring Fair Value [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	2,056,717	1,956,286
Recurring Fair Value [Member] | Level 3 [Member] | Senior Secured Loans [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	1,251,236	1,117,118
Recurring Fair Value [Member] | Level 3 [Member] | Equipment Financing [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	121,823	181,016
Recurring Fair Value [Member] | Level 3 [Member] | Preferred Equity [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	32,156	31,682
Recurring Fair Value [Member] | Level 3 [Member] | Common Equity/Equity Interests/Warrants [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	$ 651,502	$ 626,470

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