v3.26.1
Nature of Operations, Basis of Presentation, and Summary of Significant Accounting Policies (Narrative) (Details)
$ in Millions
3 Months Ended
Feb. 26, 2026
USD ($)
Jan. 26, 2026
Mar. 31, 2026
Segment
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Number of reportable segments | Segment     3
Stifel Independent Advisors, LLC [Member]      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Gain on the sale | $ $ 49.8    
O2026 Q1 Dividends [Member]      
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]      
Dividend declared date   Jan. 26, 2026  
Stock split term   three-for-two  
Dividend Declared Percentage   50.00%  
Dividend payable date   Feb. 26, 2026  
Dividend record date   Feb. 12, 2026  
Stock split description   three-for-two