v3.25.2
Commitments and Contingent Liabilities (Summary of Off-Balance Sheet Financial Instruments) (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Loss Contingencies [Line Items]    
ONE YEAR AND LESS $ 294,386.1 $ 267,669.9
OVER ONE YEAR 17,909.5 17,783.5
TOTAL 312,295.6 285,453.4
Undrawn Commitments    
Loss Contingencies [Line Items]    
Commitments, participated to others 255.5 268.5
Securities Lent with Indemnification    
Loss Contingencies [Line Items]    
ONE YEAR AND LESS 169,168.8 144,543.7
OVER ONE YEAR 0.0 0.0
TOTAL 169,168.8 144,543.7
Secured by Cash Deposits or Participated to Others | Standby Letters of Credit    
Loss Contingencies [Line Items]    
TOTAL 98.0 109.4
Standby Letter of Credit and Financial Guarantee    
Loss Contingencies [Line Items]    
Guarantor obligations, current carrying value 114,100.0 110,800.0
Undrawn Commitments    
Loss Contingencies [Line Items]    
ONE YEAR AND LESS 9,509.3 10,849.6
OVER ONE YEAR 17,549.7 17,293.2
TOTAL 27,059.0 28,142.8
Standby Letters of Credit    
Loss Contingencies [Line Items]    
ONE YEAR AND LESS 115,678.6 112,256.3
OVER ONE YEAR 359.5 490.1
TOTAL 116,038.1 112,746.4
Commercial Letters of Credit    
Loss Contingencies [Line Items]    
ONE YEAR AND LESS 29.4 20.3
OVER ONE YEAR 0.3 0.2
TOTAL $ 29.7 $ 20.5