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Derivatives - Narrative (Details) - USD ($) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2023 | Dec. 31, 2022
Derivative [Line Items] |  |
Gross amounts recognized | $ 862,316,000 | $ 755,328,000
Derivative liabilities - Fair value | 948,387,000 | 887,264,000
Derivative instruments designated as hedging instruments |  |
Derivative [Line Items] |  |
Gross amounts recognized | 4,997,000 | 19,045,000
Derivative liabilities - Fair value | 96,382,000 | 19,687,000
Notional amount | 5,081,480,000 | 3,534,832,000
Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Gross amounts recognized | 857,319,000 | 736,283,000
Derivative liabilities - Fair value | 852,005,000 | 867,577,000
Notional amount | 22,804,812,000 | 20,056,255,000
Interest rate contracts | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Gross amounts recognized | 622,799,000 | 426,828,000
Derivative liabilities - Fair value | 615,920,000 | 564,829,000
Notional amount | 17,456,102,000 | 16,932,414,000
Interest rate contracts | Derivatives not designated as hedging instruments | LCH |  |
Derivative [Line Items] |  |
Gross amounts recognized | 16,000,000.0 | 167,200,000
Derivative liabilities - Fair value | 65,700,000 | 81,300,000
Interest rate contracts | Cash Flow Hedging | Derivative instruments designated as hedging instruments |  |
Derivative [Line Items] |  |
Gross amounts recognized | 1,288,000 | 13,455,000
Derivative liabilities - Fair value | 96,382,000 | 19,687,000
Notional amount | 5,000,000,000 | 3,450,000,000
Net unrealized losses, net of tax, recorded in AOCI expected to be reclassified into earnings during next 12 months | 66,200,000 |
Foreign exchange contracts | Derivatives not designated as hedging instruments |  |
Derivative [Line Items] |  |
Gross amounts recognized | 96,668,000 | 47,519,000
Derivative liabilities - Fair value | 77,099,000 | 44,117,000
Notional amount | $ 5,205,007,000 | $ 2,982,891,000
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 | $ 0 | $ 0
Derivative liabilities - Fair value | 12,000 | 23,000
Notional amount | $ 143,703,000 | $ 140,950,000
Credit contracts | Derivatives not designated as hedging instruments | RPAs |  |
Derivative [Line Items] |  |
Weighted average remaining maturity of outstanding RPAs | 2 years 6 months | 2 years 4 months 24 days
Credit contracts | Derivatives not designated as hedging instruments | Long |  |
Derivative [Line Items] |  |
Notional amount | $ 25,000,000 | $ 0
Credit-risk-related contingent features |  |
Derivative [Line Items] |  |
Aggregate fair value of derivative instruments in net liability position | 2,200,000 | 2,600,000
Collateral posted | 2,200,000 | $ 1,100,000
Commercial Banking | Interest rate contracts | Cash Flow Hedging | Derivative instruments designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | $ 5,000,000,000 |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5C -Subparagraph (SX 210.12-13C(Column F)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5C Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 5B -Subparagraph (SX 210.12-13B(Column E)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-5B Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 22 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-22 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 + 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://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480434/815-10-50-4H + Details
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