Debt - Summary of Commitments, Borrowings Outstanding and Fair Value of Notes (Details) - Unsecured Notes - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Commitments	$ 143,110	$ 143,110
Total Amount Outstanding	143,110	143,110
Fair Value	142,269	142,809
GECCM Notes
Debt Instrument [Line Items]
Commitments	45,610	45,610
Total Amount Outstanding	45,610	45,610
Fair Value	45,738	45,793
GECCO Notes
Debt Instrument [Line Items]
Commitments	57,500	57,500
Total Amount Outstanding	57,500	57,500
Fair Value	56,235	56,792
GECCZ Notes
Debt Instrument [Line Items]
Commitments	40,000	40,000
Total Amount Outstanding	40,000	40,000
Fair Value	$ 40,296	$ 40,224