v3.26.1
N-2 - USD ($)
 9 Months Ended
Mar. 31, 2026
Dec. 31, 2025
Sep. 30, 2025
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2023
Jun. 30, 2022
Cover [Abstract]              
Entity Central Index Key 0001521945            
Amendment Flag false            
Securities Act File Number 814-00908            
Document Type 10-Q            
Entity Registrant Name Prospect Floating Rate and Alternative Income Fund, Inc.            
Entity Address, Address Line One 10 East 40th Street            
Entity Address, Address Line Two 42nd Floor            
Entity Address, City or Town New York            
Entity Address, State or Province NY            
Entity Address, Postal Zip Code 10016            
City Area Code 212            
Local Phone Number 448-0702            
Entity Emerging Growth Company false            
Financial Highlights [Abstract]              
Senior Securities [Table Text Block]
Revolving Credit FacilityTotal Amount OutstandingAsset Coverage per Unit(1)Involuntary Liquidating Preference per Unit(2)Average Market Value per Unit(2)
March 31, 2026$35,178,847 $2,005 
December 31, 2025$37,040,732 $1,937 — — 
September 30, 2025$39,246,250 $1,949 — — 
June 30, 2025$45,500,000 $1,879 — — 
June 30, 2024$27,800,000 $2,125 — — 
June 30, 2023$8,600,000 $2,709 — — 
June 30, 2022$20,500,000 $1,815 — — 
(1) The asset coverage ratio is calculated as our consolidated total assets, less all liabilities and indebtedness not represented by senior securities, divided by secured senior securities representing indebtedness. This asset coverage ratio is multiplied by $1,000 to determine the Asset Coverage Per Unit.
            
OZK Credit Facility [Member]              
Financial Highlights [Abstract]              
Senior Securities Amount $ 35,178,847 $ 37,040,732 $ 39,246,250 $ 45,500,000 $ 27,800,000 $ 8,600,000 $ 20,500,000
Senior Securities Coverage per Unit $ 2,005 $ 1,937 $ 1,949 $ 1,879 $ 2,125 $ 2,709 $ 1,815