v3.26.1
Cover
Mar. 24, 2026
Cover [Abstract]  
Document Type 8-K
Amendment Flag false
Document Period End Date Mar. 24, 2026
Entity File Number 814-00757
Entity Registrant Name FS KKR Capital Corp
Entity Central Index Key 0001422183
Entity Tax Identification Number 26-1630040
Entity Incorporation, State or Country Code MD
Entity Address, Address Line One 3025 JFK Boulevard
Entity Address, Address Line Two OFC 500
Entity Address, City or Town Philadelphia
Entity Address, State or Province PA
Entity Address, Postal Zip Code 19104
City Area Code 215
Local Phone Number 495-1150
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common stock
Trading Symbol FSK
Security Exchange Name NYSE
Entity Emerging Growth Company false