Derivatives - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Dec. 31, 2024
Derivative [Line Items]
Gross amounts recognized	$ 513,897	$ 523,133
Derivative liabilities - Fair value	464,084	545,885
Derivative instruments designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	25,982	5,647
Derivative liabilities - Fair value	12,153	35,211
Notional amount	4,250,000	5,250,000
Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	487,915	517,486
Derivative liabilities - Fair value	451,931	510,674
Notional amount	21,847,357	22,375,840
Interest rate contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	325,232	379,664
Derivative liabilities - Fair value	324,030	378,961
Notional amount	17,147,077	17,005,381
Interest rate contracts \| Derivatives not designated as hedging instruments \| LCH
Derivative [Line Items]
Gross amounts recognized	12,000	17,000
Derivative liabilities - Fair value	44,000	15,000
Interest rate contracts \| Cash Flow Hedging \| Derivative instruments designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	25,982	5,647
Derivative liabilities - Fair value	12,153	35,211
Notional amount	4,250,000	5,250,000
Net unrealized losses, net of tax, recorded in AOCI expected to be reclassified into earnings during next 12 months	5,000
Foreign exchange contracts \| Derivatives not designated as hedging instruments
Derivative [Line Items]
Gross amounts recognized	39,381	89,083
Derivative liabilities - Fair value	30,901	71,254
Notional amount	$ 4,509,409	$ 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	$ 18	$ 1
Derivative liabilities - Fair value	19	12
Notional amount	190,871	168,999
Credit contracts \| Derivatives not designated as hedging instruments \| RPAs
Derivative [Line Items]
Gross amounts recognized	0	0
Derivative liabilities - Fair value	19	12
Notional amount	140,099	133,174
Maximum exposure of RPAs with protection sold	321	170
Credit-risk-related contingent features
Derivative [Line Items]
Aggregate fair value of derivative instruments in net liability position	16,000	1,000
Collateral posted	14,000	$ 1,000
Additional collateral	2,000
Commercial Banking \| Interest rate contracts \| Cash Flow Hedging \| Derivative instruments designated as hedging instruments
Derivative [Line Items]
Notional amount	$ 4,300,000

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- Definition

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

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Maximum potential amount of future undiscounted payments that could be required under the credit derivative, before reduction for potential recoveries under recourse or collateralization provisions.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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Nominal or face amount used to calculate payment on derivative.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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