Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2024	May 07, 2024
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2024
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	Q1
Entity Registrant Name	Goldman Sachs BDC, Inc.
Entity Central Index Key	0001572694
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Small Business	false
Entity Emerging Growth Company	false
Title of 12(b) Security	Common Stock, par value$0.001 per share
Trading Symbol	GSBD
Security Exchange Name	NYSE
Entity File Number	814-00998
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	46-2176593
Entity Address, Address Line One	200 West Street
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10282
City Area Code	312
Local Phone Number	655 - 4419
Document Quarterly Report	true
Document Transition Report	false
Entity Common Stock, Shares Outstanding		112,223,204