Significant Accounting Policies - Schedule of Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Accounting Policies [Abstract]
Accelerated amortization of upfront loan origination fees and unamortized discounts	$ 2,136	$ 224

Investment income accelerated amortization of upfront loan origination fees and unamortized discounts.

No definition available.

Name:	gsbd_InvestmentIncomeAcceleratedAmortizationOfUpfrontLoanOriginationFeesAndUnamortizedDiscounts
Namespace Prefix:	gsbd_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration