v3.26.1
Fair Value of Financial Instruments (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Balance Sheet Grouping, Financial Statement Captions    
Carrying Value $ 932.5 $ 837.0
Ark 2021 Subordinated Notes    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 177.3 179.2
Carrying Value 159.0 159.7
Kudu Credit Facility    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 358.0 365.3
Carrying Value 350.7 350.4
HG Global 2026 Senior Notes    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 200.0 0.0
Carrying Value 197.4 0.0
HG Global 2022 Senior Notes    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 0.0 153.8
Carrying Value 0.0 147.8
Distinguished Credit Facility    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 132.1 131.2
Carrying Value 129.4 129.9
Distinguished other debt    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 13.1 12.2
Carrying Value 11.5 10.9
WTM Partners Debt    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 65.3 19.0
Carrying Value 66.5 19.4
Other Operations Debt    
Balance Sheet Grouping, Financial Statement Captions    
Fair Value 18.3 19.0
Carrying Value $ 18.0 $ 18.9