Derivatives - Narrative (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2025	Dec. 31, 2024
Derivative [Line Items]
Gross amounts recognized	$ 408,429	$ 523,133
Derivative liabilities - Fair value	382,202	545,885
Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	366,014	517,486
Derivative liabilities - Fair value	381,192	510,674
Notional amount	23,480,807	22,375,840
Interest rate contracts | Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	270,986	379,664
Derivative liabilities - Fair value	269,276	378,961
Notional amount	19,006,624	17,005,381
Interest rate contracts | Derivatives not designated as hedging instruments | LCH
Derivative [Line Items]
Gross amounts recognized	16,000	17,000
Derivative liabilities - Fair value	9,000	15,000
Interest rate contracts | Cash Flow Hedging | Derivative instruments designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	42,415	5,647
Derivative liabilities - Fair value	1,010	35,211
Notional amount	4,250,000	5,250,000
Net unrealized gains, net of tax, recorded in AOCI expected to be reclassified into earnings during next 12 months	3,000
Foreign exchange contracts | Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	45,999	89,083
Derivative liabilities - Fair value	40,964	71,254
Notional amount	$ 4,263,978	$ 5,201,460
Foreign exchange contracts | Derivatives not designated as hedging instruments | Maximum
Derivative [Line Items]
Original maturity (in years)	1 year	1 year
Credit contracts | Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	$ 17	$ 1
Derivative liabilities - Fair value	58	12
Notional amount	210,205	168,999
Credit contracts | Derivatives not designated as hedging instruments | RPAs
Derivative [Line Items]
Gross amounts recognized	0	0
Derivative liabilities - Fair value	58	12
Notional amount	146,126	133,174
Maximum exposure of RPAs with protection sold	641	170
Credit-risk-related contingent features
Derivative [Line Items]
Aggregate fair value of derivative instruments in net liability position	5,000	1,000
Collateral posted	4,000	$ 1,000
Additional collateral	1,000
Commercial Banking | Interest rate contracts | Cash Flow Hedging | Derivative instruments designated as hedging instruments
Derivative [Line Items]
Notional amount	$ 4,300,000