v3.26.3
Bank Loans (Schedule of Balance and Associated Percentage of Each Major Loan Category in Bank Loan Portfolio) (Details) - USD ($)
$ in Thousands
Sep. 30, 2026
Jun. 30, 2026
Dec. 31, 2025
Sep. 30, 2025
Jun. 30, 2025
Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 25,866,033   $ 22,066,763      
Loans in process/(unapplied loan payments), net (14,417)   (10,779)      
Unamortized loan fees, net (2,640)   1,518      
Allowance for credit losses on loans (113,147) $ (120,685) (132,245) $ (134,022) $ (135,734) $ (139,308)
Loans held for investment, net $ 25,735,829   $ 21,925,257      
Gross bank loans, Percent 100.00%   100.00%      
Residential Real Estate [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 9,821,336   $ 9,254,939      
Allowance for credit losses on loans $ (10,294) (12,389) $ (11,264) (12,509) (13,767) (11,061)
Gross bank loans, Percent 38.00%   41.90%      
Fund Banking [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 6,719,233   $ 4,096,649      
Allowance for credit losses on loans $ (9,985) (8,809) $ (8,193) (10,816) (10,948) (10,792)
Gross bank loans, Percent 26.00%   18.60%      
Commercial and Industrial [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 4,720,505   $ 4,135,091      
Allowance for credit losses on loans $ (76,467) (79,053) $ (92,612) (85,830) (84,981) (92,698)
Gross bank loans, Percent 18.20%   18.70%      
Securities-Based Loans [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 2,992,963   $ 2,672,431      
Allowance for credit losses on loans $ (3,139) (3,509) $ (3,254) (3,180) (3,128) (2,917)
Gross bank loans, Percent 11.60%   12.10%      
Construction And Land [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 926,412   $ 1,214,450      
Allowance for credit losses on loans $ (6,550) (10,687) $ (10,567) (12,225) (12,854) (12,866)
Gross bank loans, Percent 3.60%   5.50%      
Commercial Real Estate [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 372,212   $ 423,474      
Allowance for credit losses on loans $ (5,774) (4,919) $ (5,650) (8,603) (8,795) (8,057)
Gross bank loans, Percent 1.40%   1.90%      
Home Equity Lines Of Credit [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 261,243   $ 225,196      
Allowance for credit losses on loans $ (312) (740) $ (134) (243) (660) (317)
Gross bank loans, Percent 1.00%   1.00%      
Other [Member]            
Accounts, Notes, Loans and Financing Receivable [Line Items]            
Total risk category of loan portfolio $ 52,129   $ 44,533      
Allowance for credit losses on loans $ (626) $ (579) $ (571) $ (616) $ (601) $ (600)
Gross bank loans, Percent 0.20%   0.30%