v3.26.1
Investments - Additional Information (Details)
1 Months Ended 3 Months Ended 6 Months Ended 12 Months Ended
May 31, 2025
USD ($)
Nov. 30, 2025
USD ($)
Apr. 30, 2025
USD ($)
Dec. 31, 2024
USD ($)
Apr. 30, 2023
USD ($)
Mar. 31, 2026
USD ($)
Portfolio
Mar. 31, 2025
USD ($)
Mar. 31, 2026
USD ($)
Portfolio
Mar. 31, 2025
USD ($)
Sep. 30, 2025
USD ($)
Portfolio
Feb. 28, 2026
USD ($)
Oct. 29, 2025
USD ($)
May 31, 2024
USD ($)
Jan. 31, 2021
USD ($)
Schedule Of Investments [Line Items]                            
Purchases of investments, including PIK interest           $ 296,300,000 $ 295,000,000 $ 599,000,000 $ 903,300,000          
Sales and repayments of investments           328,000,000 $ 122,400,000 769,500,000 $ 523,700,000          
Total assets           2,747,936,000   2,747,936,000   $ 2,913,681,000        
Fair market capital contributions           0   $ 39,400,000            
Number of members appointed               four            
Quorum description               Quorum is defined as (i) the presence of two members of the board of directors or investment committee, provided that at least one individual is present that was elected, designated or appointed by each member; (ii) the presence of three members of the board of directors or investment committee, provided that the individual that was elected, designated or appointed by the member with only one individual present shall be entitled to cast two votes on each matter; and (iii) the presence of four members of the board of directors or investment committee constitutes a quorum, provided that two individuals are present that were elected, designated or appointed by each member            
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)           328,333,000   $ 328,333,000   683,837,000        
Credit facility interest rate description       SOFR plus 225 basis points                    
Debt securitization         $ 297,800,000             $ 21,000,000 $ 300,700,000 $ 300,700,000
Pennant Park C L O I I Ltd                            
Schedule Of Investments [Line Items]                            
Asset backed debt, transfer of assets, description               2032. On the closing date of the transaction, in consideration of PSSL’s transfer to PennantPark CLO II, Ltd. of the initial closing date loan portfolio, which included loans distributed to PSSL by certain of its wholly owned subsidiaries and us, PennantPark CLO II, Ltd. transferred to PSSL 100% of the Preferred Shares of PennantPark CLO II, Ltd. and 100% of the Class E Notes issued by PennantPark CLO II, Ltd.            
PennantPark CLO VI, LLC                            
Schedule Of Investments [Line Items]                            
Asset backed debt, transfer of assets, description         2035. On the closing date of the transaction, in consideration of PSSL’s transfer to PennantPark CLO VI, LLC of the initial closing date loan portfolio, which included loans distributed to PSSL by certain of its wholly owned subsidiaries and us, PennantPark CLO VI, LLC transferred to PSSL 100% of the Preferred Shares of CLO VI, LLC, all of which were held by PSSL.                  
Debt instrument $ 315,800,000                          
PennantPark CLO VI, LLC | Class Loans A-R                            
Schedule Of Investments [Line Items]                            
Debt instrument $ 228,000,000                          
Interest rate 1.85%                          
PennantPark CLO VI, LLC | Class Loans B-R                            
Schedule Of Investments [Line Items]                            
Debt instrument $ 18,000,000                          
PennantPark CLO VI, LLC | Class Loans C-R                            
Schedule Of Investments [Line Items]                            
Debt instrument $ 18,000,000                          
Interest rate 4.50%                          
PennantPark CLO VI, LLC | Sub Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument $ 51,800,000                          
PennantPark CLO 12, LLC                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 301,000,000                      
Issuance date     2029-04                      
Maturity date     2037-04                      
Secured credit facility     $ 325,000,000                      
PennantPark CLO 12, LLC | Class A-1 Loans                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 30,000,000                      
Interest rate     1.45%                      
PennantPark CLO 12, LLC | Class A-1 Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 141,000,000                      
Interest rate     1.45%                      
PennantPark CLO 12, LLC | Class A-2 Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 12,000,000                      
Interest rate     1.60%                      
PennantPark CLO 12, LLC | Class B Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 21,000,000                      
Interest rate     1.85%                      
PennantPark CLO 12, LLC | Class C Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 24,000,000                      
Interest rate     2.30%                      
PennantPark CLO 12, LLC | Class D Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 18,000,000                      
Interest rate     3.30%                      
PennantPark CLO 12, LLC | Sub Notes                            
Schedule Of Investments [Line Items]                            
Debt instrument     $ 55,000,000                      
Senior Secured Revolving Credit Facility                            
Schedule Of Investments [Line Items]                            
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)       $ 260,000,000                    
PennantPark Senior Secured Loan Fund I LLC                            
Schedule Of Investments [Line Items]                            
Total assets           $ 1,248,767,000   $ 1,248,767,000   $ 1,153,689,000        
Number of portfolio companies consisted of debt investments | Portfolio           120   120   117        
Percentage of capital ownership in each of outstanding subordinated notes and equity interests               87.50%   12.50%        
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)           $ 158,500,000   $ 158,500,000   $ 74,500,000        
PennantPark Senior Secured Loan Fund I LLC | Senior Secured Revolving Credit Facility                            
Schedule Of Investments [Line Items]                            
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)       $ 325,000,000                    
PennantPark Senior Secured Loan Fund I LLC | Investment In Single Portfolio Company                            
Schedule Of Investments [Line Items]                            
Fair value of largest investment in a single portfolio company           24,900,000   24,900,000   20,900,000        
PennantPark Senior Secured Loan Fund I LLC | Five Largest Investments                            
Schedule Of Investments [Line Items]                            
Fair value of investment in five largest portfolio company           111,900,000   111,900,000   99,300,000        
PennantPark Senior Secured Loan Fund I LLC | First Lien Secured Debt                            
Schedule Of Investments [Line Items]                            
Total investments           237,700,000   237,700,000   237,700,000        
Additional unfunded investment           0   0   0        
PennantPark Senior Secured Loan Fund I LLC | Equity Interests                            
Schedule Of Investments [Line Items]                            
Total investments           163,100,000   163,100,000   123,700,000        
Additional unfunded investment in equity           26,300,000   26,300,000   $ 65,600,000        
Pennant Park Senior Secured Loan Fund II L L C [Member]                            
Schedule Of Investments [Line Items]                            
Total assets           357,509,000   357,509,000            
Total investments           200,000,000   200,000,000            
Fair market capital contributions           37,500,000   37,500,000            
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)           226,000,000   226,000,000            
Secured debt           105,000,000   105,000,000            
Investment Membership Interest Amount           45,000,000   45,000,000            
Equity securities at fair value           28,100,000   28,100,000            
Unfunded debt commitment           39,400,000   39,400,000            
Unfunded Equity Commitment           16,900,000   16,900,000            
Pennant Park Senior Secured Loan Fund II L L C [Member] | Revolving Credit Facility                            
Schedule Of Investments [Line Items]                            
Credit Facility payable, at fair value (cost - $328,355 and $683,855, respectively)   $ 150,000,000                 $ 250,000,000      
Interest rate   1.85%                        
Pennant Park Senior Secured Loan Fund II L L C [Member] | Investment In Single Portfolio Company                            
Schedule Of Investments [Line Items]                            
Total investments           13,000,000   13,000,000            
Pennant Park Senior Secured Loan Fund II L L C [Member] | Five Largest Investments                            
Schedule Of Investments [Line Items]                            
Total investments           64,800,000   64,800,000            
Pennant Park Senior Secured Loan Fund II L L C [Member] | First Lien Secured Debt                            
Schedule Of Investments [Line Items]                            
first lien secured debt           65,600,000   65,600,000            
Pennant Park Senior Secured Loan Fund II L L C [Member] | Investments Fair Value [Member]                            
Schedule Of Investments [Line Items]                            
Fair market capital contributions           93,800   93,800            
PennantPark Floating Rate Capital Ltd [Member]                            
Schedule Of Investments [Line Items]                            
Total investments           150,000,000   150,000,000            
Hamilton Lane [Member]                            
Schedule Of Investments [Line Items]                            
Total investments           50,000,000   50,000,000            
Secured debt           35,000,000   35,000,000            
Investment Membership Interest Amount           $ 15,000,000   $ 15,000,000