Fair Value of Financial Instruments - Summary of Company's Assets Measured at Fair Value by Investment Type on a Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	$ 1,093,063	$ 794,509
Fair Value, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	1,094,386	873,470
Escrow Receivable	2,441	4,152
Cash, cash equivalents and restricted cash	10,612	46,742
Total	1,107,439	924,364
Fair Value, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	588
Cash, cash equivalents and restricted cash	10,612	46,742
Total	11,200	46,742
Fair Value, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	735	78,961
Total	735	78,961
Fair Value, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	1,093,063	794,509
Escrow Receivable	2,441	4,152
Total	1,095,504	798,661
Fair Value, Recurring | Secured Loans
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	802,851	551,894
Fair Value, Recurring | Secured Loans | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	802,851	551,894
Fair Value, Recurring | Equipment Financing
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	245,978	184,074
Fair Value, Recurring | Equipment Financing | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	245,978	184,074
Fair Value, Recurring | Warrants
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	31,724	36,770
Fair Value, Recurring | Warrants | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	735	17
Fair Value, Recurring | Warrants | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	30,989	36,753
Fair Value, Recurring | Equity
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	13,833	100,732
Fair Value, Recurring | Equity | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	588
Fair Value, Recurring | Equity | Significant Other Observable Inputs (Level 2)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value		78,944
Fair Value, Recurring | Equity | Significant Unobservable Inputs (Level 3)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Total Investments at fair value	$ 13,245	$ 21,788