v3.26.1
Borrowings - Narrative (Details) - USD ($)
6 Months Ended
May 15, 2026
May 12, 2026
Jun. 13, 2025
Feb. 18, 2025
Jan. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Jun. 14, 2024
Line of Credit Facility [Line Items]                  
Short-term borrowings           $ 0   $ 498,415,000  
Repayment of unsecured debt           $ 498,851,000 $ 500,000,000    
Vertical risk retention interest           5.00%      
Uncommitted federal funds           $ 125,000,000      
Lendable value of collateral           2,200,000,000   2,500,000,000  
Unsecured borrowings                  
Line of Credit Facility [Line Items]                  
Short-term borrowings           0   498,415,000  
Secured Borrowings | Line of Credit                  
Line of Credit Facility [Line Items]                  
Short-term borrowings           0   $ 0  
Secured borrowing facility maximum borrowing capacity     $ 2,500,000,000           $ 2,000,000,000
Line of credit facility, interest holding percentage     100.00%            
Senior Unsecured Notes Due January 31, 2030 | Unsecured borrowings                  
Line of Credit Facility [Line Items]                  
Notes Issued         $ 500,000,000        
Debt instrument, interest rate, stated percentage         6.50%        
Debt instrument, issuance price, percentage         99.78%        
Unsecured debt           494,000,000      
Senior Unsecured Notes Due October 29, 2025 | Unsecured borrowings                  
Line of Credit Facility [Line Items]                  
Debt instrument, interest rate, stated percentage       4.20%          
Repayments of long-term debt       $ 500,000,000          
Debt instrument, redemption price, percentage       100.00%          
Gain (loss) on extinguishment of debt       $ (1,000,000)          
Senior Unsecured Notes Due November 2, 2026 | Unsecured borrowings                  
Line of Credit Facility [Line Items]                  
Notes Issued $ 500,000,000                
Debt instrument, interest rate, stated percentage 6.495%                
Debt instrument, issuance price, percentage 100.00%                
Short-term borrowings           494,000,000      
ABCP borrowings | Secured Borrowings                  
Line of Credit Facility [Line Items]                  
Line of credit facility, expiration period     2 years            
2026 Senior Notes                  
Line of Credit Facility [Line Items]                  
Gain (loss) on extinguishment of debt           $ 1,000,000      
Repurchase principal amount $ 52,000,000                
2026 Senior Notes | Unsecured borrowings                  
Line of Credit Facility [Line Items]                  
Debt instrument, interest rate, stated percentage   3.125%              
Repurchase principal amount   $ 500,000,000              
Fair value of repurchased amount   448,000,000              
Repayment of unsecured debt   $ 447,000,000              
Percent of debt fair value   99.58%