v3.26.3
Debt and Credit Facilities - Narrative (Details) - USD ($)
3 Months Ended 9 Months Ended
Oct. 26, 2026
Oct. 23, 2025
Oct. 20, 2025
Jun. 10, 2025
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Oct. 05, 2026
Nov. 15, 2024
Jun. 23, 2022
Line of Credit Facility [Line Items]                      
Line of credit facility, outstanding         $ 783,578,000   $ 783,578,000        
Interest expense         4,801,000 $ 4,933,000 14,339,000 $ 15,264,000      
Unsecured Debt | Facility                      
Line of Credit Facility [Line Items]                      
Face amount       $ 150,000,000             $ 150,000,000
Amortization of debt issuance costs         100,000 $ 100,000 100,000 $ 100,000      
Line of Credit | Uncommitted Secured Letter Of Credit Facility | Letter of Credit                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity                   $ 250,000,000  
Line of Credit | Uncommitted Secured Letter Of Credit Facility | Letter of Credit | Subsequent Event                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity                 $ 325,000,000    
Line of Credit | Unsecured Facility                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity       $ 450,000,000              
Line of credit facility, outstanding         $ 0   $ 0        
Unused commitment fee percentage       0.175%              
Line of Credit | Unsecured Facility | Letter of Credit                      
Line of Credit Facility [Line Items]                      
Stated interest rate       1.25%              
Line of Credit | Unsecured Facility | Revolving Credit Facility                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity       $ 150,000,000              
Line of Credit | Unsecured Facility | Revolving Credit Facility | Prime Rate                      
Line of Credit Facility [Line Items]                      
Basis spread on variable rate       0.50%              
Line of Credit | Unsecured Facility | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)                      
Line of Credit Facility [Line Items]                      
Basis spread on variable rate       1.50%              
Line of Credit | UBS Letter of Credit Facility | Letter of Credit                      
Line of Credit Facility [Line Items]                      
Commitment fee percentage   1.40%                  
Line of Credit | UBS Letter of Credit Facility | Letter of Credit | Minimum                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity   $ 25,000,000                  
Line of Credit | UBS Letter of Credit Facility | Letter of Credit | Maximum                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity   $ 75,000,000                  
Line of Credit | Unsecured Facility, Lloyd's | Letter of Credit                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity     $ 260,000,000                
Commitment fee percentage     1.50%                
Renewal term     4 years                
Line of Credit | Unsecured Facility, Lloyd's | Letter of Credit | Subsequent Event                      
Line of Credit Facility [Line Items]                      
Line of credit facility, maximum borrowing capacity $ 330,000,000                    
Commitment fee percentage 1.50%