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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 |

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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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 185 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-185 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4H -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 185 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-185 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4H -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 185 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480401/815-10-55-185 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4H -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4H + Details
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