v3.25.2
Note 7 - Goodwill and Intangible Assets - Intangible Assets and Goodwill (Details) - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Intangible assets, amortization $ (5.5) $ (0.2)
Accumulated amortization, balance (62.8) (62.1)
Foreign currency translation, accumulated amortization (4.5) (0.7)
Accumulated amortization, balance (72.8) (61.6)
Net intangible assets, balance 2,473.3 2,431.3
Net intangible assets 41.1  
Foreign currency translation, Net intangible assets 31.6 (3.5)
Net intangible assets, balance 2,540.5 2,427.6
Goodwill, balance 1,550.4 1,290.3
Goodwill, addition 17.8  
Foreign currency translation, Goodwill 65.6 (6.5)
Goodwill, balance 1,633.8 1,283.8
Balance 92.7  
Foreign currency translation, accumulated amortization 4.5 0.7
Accumulated amortization 72.8 61.6
Client Relationships [Member]    
Balance 86.1  
Intangible assets, amortization 0.0 0.0
Additions 0.0  
Foreign currency translation, definite-lived intangible assets 4.8 (0.9)
Balance 90.9  
Balance   68.6
Foreign currency translation, definite-lived intangible assets 4.8 (0.9)
Balance   67.7
Investment Management Agreements [Member]    
Balance 28.0  
Additions 41.1  
Foreign currency translation, definite-lived intangible assets 0.0  
Balance 69.1  
Foreign currency translation, definite-lived intangible assets 0.0  
Definite Lived Trademarks [Member]    
Balance 5.5  
Additions 0.0  
Foreign currency translation, definite-lived intangible assets 0.0  
Balance 5.5  
Foreign currency translation, definite-lived intangible assets 0.0  
Investment Management Agreements [Member]    
Balance 2,056.5 2,064.8
Foreign currency translation, indefinite-lived intangible assets 31.3 (3.3)
Balance 2,087.8 2,061.5
Foreign currency translation 31.3 (3.3)
Trademarks [Member]    
Balance 360.0 360.0
Foreign currency translation, indefinite-lived intangible assets 0.0 0.0
Balance 360.0 360.0
Foreign currency translation $ 0.0 $ 0.0