v3.26.3
Bank Loans (Aging of the Recorded Investment in Past Due Loans) (Details) - USD ($)
$ in Thousands
Sep. 30, 2026
Dec. 31, 2025
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans $ 25,866,033 $ 22,066,763
Nonperforming loans with allowance 71,248 81,465
Nonperforming loans with no allowance 54,259 43,694
Total 125,507 125,159
30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 41,861 70,094
90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 25,383 104,676
Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 67,244 174,770
Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 25,798,789 21,891,993
Residential Real Estate [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 9,821,336 9,254,939
Nonperforming loans with allowance 2,412 1,033
Nonperforming loans with no allowance   2,455
Total 2,412 3,488
Residential Real Estate [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 27,247 16,269
Residential Real Estate [Member] | 90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 2,412 3,488
Residential Real Estate [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 29,659 19,757
Residential Real Estate [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 9,791,677 9,235,182
Fund Banking [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 6,719,233 4,096,649
Fund Banking [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 8,016 1,774
Fund Banking [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 8,016 1,774
Fund Banking [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 6,711,217 4,094,875
Commercial and Industrial [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 4,720,505 4,135,091
Nonperforming loans with allowance 68,638 80,429
Nonperforming loans with no allowance 7,623 2,307
Total 76,261 82,736
Commercial and Industrial [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 5,380 51,000
Commercial and Industrial [Member] | 90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 22,711 55,236
Commercial and Industrial [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 28,091 106,236
Commercial and Industrial [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 4,692,414 4,028,855
Securities-Based Loans [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 2,992,963 2,672,431
Securities-Based Loans [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 882 514
Securities-Based Loans [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 882 514
Securities-Based Loans [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 2,992,081 2,671,917
Commercial Real Estate [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 372,212 423,474
Commercial Real Estate [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 372,212 423,474
Construction And Land [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 926,412 1,214,450
Nonperforming loans with no allowance 46,574 38,417
Total 46,574 38,417
Construction And Land [Member] | 90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans   45,434
Construction And Land [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans   45,434
Construction And Land [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 926,412 1,169,016
Home Equity Lines Of Credit [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 261,243 225,196
Nonperforming loans with allowance 162  
Nonperforming loans with no allowance   515
Total 162 515
Home Equity Lines Of Credit [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 323 499
Home Equity Lines Of Credit [Member] | 90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 162 515
Home Equity Lines Of Credit [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 485 1,014
Home Equity Lines Of Credit [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 260,758 224,182
Other [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 52,129 44,533
Nonperforming loans with allowance 36 3
Nonperforming loans with no allowance 62  
Total 98 3
Other [Member] | 30 - 89 Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 13 38
Other [Member] | 90 or More Days Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 98 3
Other [Member] | Financial Asset, Past Due [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans 111 41
Other [Member] | Current Balance [Member]    
Financing Receivable Recorded Investment Past Due [Line Items]    
Total gross bank loans $ 52,018 $ 44,492