XML 184 R62.htm IDEA: XBRL DOCUMENT v3.23.3
Goodwill and Other Intangible Assets - Schedule of Acquisition Date Fair Values, Accumulated Amortization and Net Carrying Values for Other Intangibles Assets and Goodwill, By Company (Details) - USD ($)
$ in Millions
 9 Months Ended
Sep. 30, 2023
Jun. 30, 2023
Dec. 31, 2022
Sep. 30, 2022
Jun. 30, 2022
Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items]            
Goodwill $ 168.8 $ 168.8 $ 176.5 $ 175.5 $ 201.8 $ 142.3
Other intangible assets, finite-lived, accumulated amortization 15.5   12.2      
Total other intangible assets 218.8   228.1      
Total other intangible assets 203.3 204.8 215.9 217.7 196.2 198.2
Total goodwill and other intangible assets 387.6   404.6      
Goodwill and other intangible assets 372.1 $ 373.6 392.4 $ 393.2 $ 398.0 $ 340.5
Other            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, finite-lived, accumulated amortization 15.5   12.2      
Total other intangible assets 203.3   215.9      
Operating Segments | P&C Insurance and Reinsurance (Ark/WM Outrigger)            
Acquired Finite-Lived Intangible Assets [Line Items]            
Goodwill and other intangible assets 292.5   292.5      
Operating Segments | P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark            
Acquired Finite-Lived Intangible Assets [Line Items]            
Goodwill 116.8   116.8      
Operating Segments | P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark | Underwriting Capacity            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, indefinite-lived 175.7   175.7      
Operating Segments | Kudu            
Acquired Finite-Lived Intangible Assets [Line Items]            
Goodwill 7.6   7.6      
Goodwill and other intangible assets $ 8.4   8.6      
Operating Segments | Kudu | Trade names            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, weighted average useful life (in years) 7 years          
Other intangible assets, finite-lived, acquisition date fair value $ 2.2   2.2      
Other intangible assets, finite-lived, accumulated amortization 1.4   1.2      
Other intangible assets, finite-lived, net carrying value 0.8   1.0      
Other Operations            
Acquired Finite-Lived Intangible Assets [Line Items]            
Goodwill 44.4   52.1      
Other intangible assets, finite-lived, acquisition date fair value 40.9   50.2      
Other intangible assets, finite-lived, accumulated amortization 14.1   11.0      
Other intangible assets, finite-lived, net carrying value 26.8   39.2      
Goodwill and other intangible assets $ 71.2   91.3      
Other Operations | Trade names            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, weighted average useful life (in years) 13 years 3 months 18 days          
Other intangible assets, finite-lived, acquisition date fair value $ 13.3   17.9      
Other intangible assets, finite-lived, accumulated amortization 3.7   3.0      
Other intangible assets, finite-lived, net carrying value $ 9.6   14.9      
Other Operations | Customer relationships            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, weighted average useful life (in years) 10 years 10 months 24 days          
Other intangible assets, finite-lived, acquisition date fair value $ 24.8   29.5      
Other intangible assets, finite-lived, accumulated amortization 9.4   7.5      
Other intangible assets, finite-lived, net carrying value $ 15.4   22.0      
Other Operations | Other            
Acquired Finite-Lived Intangible Assets [Line Items]            
Other intangible assets, weighted average useful life (in years) 12 years 1 month 6 days          
Other intangible assets, finite-lived, acquisition date fair value $ 2.8   2.8      
Other intangible assets, finite-lived, accumulated amortization 1.0   0.5      
Other intangible assets, finite-lived, net carrying value $ 1.8   $ 2.3