Annual report pursuant to Section 13 and 15(d)

RELATED-PARTY TRANSACTIONS - Narrative (Details)

v3.25.0.1
RELATED-PARTY TRANSACTIONS - Narrative (Details)
$ / shares in Units, $ in Thousands
 12 Months Ended
Nov. 09, 2022
Dec. 31, 2024
USD ($)
$ / shares
Dec. 31, 2023
USD ($)
$ / shares
Dec. 31, 2022
USD ($)
Series C Preferred Stock        
Related Party Transaction [Line Items]        
Preferred stock, par value (in dollars per share)   $ 0.001 $ 0.001  
Series E Preferred Stock        
Related Party Transaction [Line Items]        
Preferred stock, par value (in dollars per share)   $ 0.001 $ 0.001  
Series E Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Dividend rate 5.00%      
Gladstone Securities        
Related Party Transaction [Line Items]        
Notice period for termination of agreement without cause   120 days    
Termination agreement, percentage of independent directors   66.67%    
Multiplier   3    
Period prior to termination   24 months    
Advisory Agreement - Base Rate, Annualized Rate | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, base rate   0.60%    
Advisory Agreement - Base Rate, Quarterly Rate | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, base rate   0.15%    
Advisory Agreement - Incentive Rate, Quarterly Hurdle Rate | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   1.75%    
Advisory Agreement - Incentive Rate, Annualized Hurdle Rate | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   7.00%    
Advisory Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Below Catch-Up Threshold | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   100.00%    
Advisory Agreement - Incentive Rate, Quarterly Catch-Up Threshold | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   2.1875%    
Advisory Agreement - Incentive Rate, Annualized Catch-Up Threshold | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   8.75%    
Advisory Agreement - Incentive Rate, Pre-Incentive Fee Net Investment Income Exceeds Catch-Up Threshold | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   20.00%    
Advisory Agreement - Incentive Rate, Realized Capital Gains | Gladstone Securities        
Related Party Transaction [Line Items]        
Management and service fees, incentive rate   15.00%    
Financing Fees        
Related Party Transaction [Line Items]        
Total due to related parties | $   $ 0 $ 0 $ 154
Financing Arrangement Agreement, Percentage of Gross Proceeds | Gladstone Securities | Minimum        
Related Party Transaction [Line Items]        
Related party transaction, rate   0.50%    
Financing Arrangement Agreement, Percentage of Gross Proceeds | Gladstone Securities | Maximum        
Related Party Transaction [Line Items]        
Related party transaction, rate   1.00%    
Financing Arrangement Agreement, Percentage Of Financing Fees Paid        
Related Party Transaction [Line Items]        
Related party transaction, rate   0.14%    
Dealer-Manager Agreements | Series C Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Preferred stock, par value (in dollars per share)   $ 0.001    
Dividend rate   6.00%    
Dealer-Manager Agreements | Series E Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Preferred stock, par value (in dollars per share)   $ 0.001    
Dividend rate   5.00%    
Dealer-Manager Agreements, Selling Commissions of Gross Proceeds from Sales | Series C Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Related party transaction, rate   6.00%    
Dealer-Manager Agreements, Selling Commissions of Gross Proceeds from Sales | Series E Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Related party transaction, rate   7.00%    
Dealer-Manager Agreements, Dealer-Manager Fee of Gross Proceeds from Sales | Series C Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Related party transaction, rate   3.00%    
Dealer-Manager Agreements, Dealer-Manager Fee of Gross Proceeds from Sales | Series E Preferred Stock | Preferred Stock        
Related Party Transaction [Line Items]        
Related party transaction, rate   3.00%