v3.26.1
Debt - Schedule of Debt (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2026
USD ($)
agreement
extension
Dec. 31, 2025
USD ($)
Mar. 13, 2026
USD ($)
Feb. 06, 2026
USD ($)
Jun. 30, 2025
USD ($)
Sep. 17, 2021
USD ($)
Fixed Rate            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured notes         $ 82,000,000.0  
Interest rate, stated percentage         8.25%  
Floating Rate            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured notes         $ 25,000,000.0  
Interest rate, effective percentage 4.00%          
Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 4,275,000,000 $ 4,000,000,000        
Unsecured debt, amount outstanding 1,495,300,000 1,087,087,000        
Interest Expense $ 18,240,000 $ 53,500,000        
Ending Weighted Average Interest Rate 5.63% 5.70%        
Mortgage note payable            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding $ 23,998,000 $ 23,998,000        
Interest Expense $ 407,000 $ 1,783,000        
Ending Weighted Average Interest Rate 6.79% 6.87%        
Mortgage note payable | Industrial | Jeffersonville, GA            
Assets Sold under Agreements to Repurchase [Line Items]            
Principal amount           $ 112,700,000
Mortgage note payable | September 2021 Mortgage Note Payable, Eliminated in Consolidation | Industrial | Jeffersonville, GA | Franklin BSP Realty Trust, Inc            
Assets Sold under Agreements to Repurchase [Line Items]            
Principal amount           $ 88,700,000
Other financings            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding $ 12,865,000 $ 12,865,000        
Interest Expense $ 193,000 $ 783,000        
Ending Weighted Average Interest Rate 6.00% 6.00%        
Number of note-on-note financings | agreement 1          
Unsecured Debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding $ 189,500,000 $ 189,500,000        
Interest Expense $ 3,916,000 $ 12,808,000        
Ending Weighted Average Interest Rate 7.75% 7.81%        
Interest paid on unsecured debt $ 1,500,000          
Unsecured Debt | Unsecured Senior Notes I            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding 107,000,000 $ 107,000,000        
Interest Expense 2,381,000 6,158,000        
Unsecured Debt | Junior Note I            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding 17,500,000 17,500,000        
Interest Expense $ 337,000 $ 1,458,000        
Ending Weighted Average Interest Rate 7.43% 7.60%        
Unsecured Debt | Junior Note II            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding $ 40,000,000 $ 40,000,000        
Interest Expense $ 737,000 $ 3,195,000        
Ending Weighted Average Interest Rate 7.24% 7.28%        
Unsecured Debt | Junior Note III            
Assets Sold under Agreements to Repurchase [Line Items]            
Unsecured debt, amount outstanding $ 25,000,000 $ 25,000,000        
Interest Expense $ 461,000 $ 1,997,000        
Ending Weighted Average Interest Rate 7.24% 7.28%        
Secured debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Advance rate of mortgage loan (percent) 100.00%          
Secured debt | Minimum            
Assets Sold under Agreements to Repurchase [Line Items]            
Advance rate of mortgage loan (percent) 60.00%          
Secured debt | Maximum            
Assets Sold under Agreements to Repurchase [Line Items]            
Advance rate of mortgage loan (percent) 75.00%          
Repo Facility | JPM Repo Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 750,000,000 $ 500,000,000        
Unsecured debt, amount outstanding 619,179,000 439,408,000        
Interest Expense $ 8,452,000 $ 18,107,000        
Ending Weighted Average Interest Rate 5.80% 6.04%        
Repo Facility | JPM Repo Facility | Secured debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity       $ 750,000,000.0    
Line Of Credit Facility, Additional Borrowing Capacity       $ 250,000,000.0    
Number of extension options | extension 2          
Extension period on initial maturity date 1 year          
Repo Facility | Atlas Repo Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 350,000,000 $ 350,000,000        
Unsecured debt, amount outstanding 211,827,000 150,744,000        
Interest Expense $ 3,649,000 $ 10,598,000        
Ending Weighted Average Interest Rate 6.17% 6.35%        
Repo Facility | WF Repo Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 250,000,000 $ 250,000,000        
Unsecured debt, amount outstanding 165,220,000 75,172,000        
Interest Expense $ 1,809,000 $ 1,749,000        
Ending Weighted Average Interest Rate 5.11% 5.22%        
Repo Facility | WF Repo Facility | Secured debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Number of extension options | extension 3          
Extension period on initial maturity date 1 year          
Repo Facility | Barclays Revolver Facility | Secured debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Number of extension options | extension 1          
Extension period on initial maturity date 1 year          
Repo Facility | Barclays Repo Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 500,000,000 $ 500,000,000        
Unsecured debt, amount outstanding 154,942,000 82,602,000        
Interest Expense $ 1,400,000 $ 8,889,000        
Ending Weighted Average Interest Rate 5.31% 5.59%        
Repo Facility | Churchill Repo Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 0 $ 0        
Unsecured debt, amount outstanding 0 0        
Interest Expense 0 555,000        
Repo Facility | Fifth Third Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity   100,000,000        
Unsecured debt, amount outstanding   15,000,000        
Interest Expense   1,265,000        
Repo Facility | Fifth Third Line of Credit | Secured debt            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity     $ 125,000,000.0      
Line Of Credit Facility, Additional Borrowing Capacity     $ 25,000,000.0      
Repo Facility | PNC WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity   500,000,000        
Unsecured debt, amount outstanding   47,924,000        
Interest Expense   $ 1,628,000        
Ending Weighted Average Interest Rate   4.99%        
Repo Facility | ASAP WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity   $ 100,000,000        
Unsecured debt, amount outstanding   0        
Interest Expense   0        
Revolver Facility | Barclays Revolver Facility | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity 100,000,000 100,000,000        
Unsecured debt, amount outstanding 0 0        
Interest Expense 31,000 438,000        
Revolver Facility | JPM WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity   700,000,000        
Unsecured debt, amount outstanding   222,831,000        
Interest Expense   $ 5,892,000        
Ending Weighted Average Interest Rate   5.04%        
Line of Credit | BAML WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity 500,000,000 $ 500,000,000        
Unsecured debt, amount outstanding 55,105,000 9,399,000        
Interest Expense $ 398,000 $ 1,210,000        
Ending Weighted Average Interest Rate 4.97% 5.17%        
Line of Credit | Fifth Third WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 400,000,000 $ 400,000,000        
Unsecured debt, amount outstanding 87,419,000 44,007,000        
Interest Expense $ 369,000 $ 3,169,000        
Ending Weighted Average Interest Rate 4.98% 5.02%        
Line of Credit | Fifth Third Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 125,000,000          
Unsecured debt, amount outstanding 100,000,000          
Interest Expense $ 623,000          
Ending Weighted Average Interest Rate 6.40% 6.53%        
Line of Credit | JPM WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 700,000,000          
Unsecured debt, amount outstanding 66,345,000          
Interest Expense $ 1,012,000          
Ending Weighted Average Interest Rate 5.02%          
Line of Credit | PNC WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 500,000,000          
Unsecured debt, amount outstanding 35,263,000          
Interest Expense $ 497,000          
Ending Weighted Average Interest Rate 4.96%          
Line of Credit | ASAP WH Line of Credit | Line of Credit            
Assets Sold under Agreements to Repurchase [Line Items]            
Repo and revolving credit facilities, commercial mortgage loans, capacity $ 100,000,000          
Unsecured debt, amount outstanding 0          
Interest Expense $ 0          
Line of Credit | ASAP WH Line of Credit | Line of Credit | Secured Overnight Financing Rate (SOFR)            
Assets Sold under Agreements to Repurchase [Line Items]            
Weighted Average Spread 1.50%          
Debt Instrument, Interest Rate Floor 0.25%