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Fair Value Measurement and Fair Value of Financial Instruments - Financial Assets and Liabilities Measurement on Recurring Basis (Details) - USD ($) $ in Thousands | Mar. 31, 2023 | Dec. 31, 2022
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Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Total investments in tax credit and other investments | $ 741,354 | $ 763,256
Derivative |  |
Derivative assets - Fair value | 627,402 | 755,328
Net derivative assets | 262,275 | 140,545
Derivative liabilities - Fair value | 681,830 | 887,264
Net derivative liabilities | 511,981 | 644,519
Fair Value, Measurements, Recurring |  |
Available-for-sale debt securities |  |
Fair Value | 6,300,868 | 6,034,993
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 24,421 | 23,954
Total investments in tax credit and other investments | 24,421 | 23,954
Derivative |  |
Derivative assets - Fair value | 627,402 | 755,328
Netting adjustments | (365,127) | (614,783)
Net derivative assets | 262,275 | 140,545
Derivative liabilities - Fair value | 681,830 | 887,264
Netting adjustments | (169,849) | (242,745)
Net derivative liabilities | 511,981 | 644,519
Fair Value, Measurements, Recurring | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 415,000 | 440,283
Derivative liabilities - Fair value | 462,411 | 584,516
Fair Value, Measurements, Recurring | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 34,050 | 53,109
Derivative liabilities - Fair value | 32,791 | 44,117
Fair Value, Measurements, Recurring | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 277 | 323
Fair Value, Measurements, Recurring | Credit contracts |  |
Derivative |  |
Derivative liabilities - Fair value | 29 | 23
Fair Value, Measurements, Recurring | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 178,075 | 261,613
Derivative liabilities - Fair value | 186,599 | 258,608
Fair Value, Measurements, Recurring | U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 916,982 | 606,203
Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 463,860 | 461,607
Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 497,115 | 500,269
Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 1,772,082 | 1,762,195
Fair Value, Measurements, Recurring | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 266,015 | 257,099
Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 396,723 | 398,329
Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 638,409 | 649,224
Fair Value, Measurements, Recurring | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 516,253 | 526,274
Fair Value, Measurements, Recurring | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 185,883 | 227,053
Fair Value, Measurements, Recurring | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 46,307 | 49,076
Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 601,239 | 597,664
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Available-for-sale debt securities |  |
Fair Value | 916,982 | 606,203
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 20,204 | 19,777
Total investments in tax credit and other investments | 20,204 | 19,777
Derivative |  |
Derivative assets - Fair value | 0 | 0
Netting adjustments | 0 | 0
Net derivative assets | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Netting adjustments | 0 | 0
Net derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Credit contracts |  |
Derivative |  |
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 916,982 | 606,203
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) |  |
Available-for-sale debt securities |  |
Fair Value | 5,383,886 | 5,428,790
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 4,217 | 4,177
Total investments in tax credit and other investments | 4,217 | 4,177
Derivative |  |
Derivative assets - Fair value | 627,125 | 755,005
Netting adjustments | (365,127) | (614,783)
Net derivative assets | 261,998 | 140,222
Derivative liabilities - Fair value | 681,830 | 887,264
Netting adjustments | (169,849) | (242,745)
Net derivative liabilities | 511,981 | 644,519
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 415,000 | 440,283
Derivative liabilities - Fair value | 462,411 | 584,516
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 34,050 | 53,109
Derivative liabilities - Fair value | 32,791 | 44,117
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Credit contracts |  |
Derivative |  |
Derivative liabilities - Fair value | 29 | 23
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 178,075 | 261,613
Derivative liabilities - Fair value | 186,599 | 258,608
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 463,860 | 461,607
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 497,115 | 500,269
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 1,772,082 | 1,762,195
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 266,015 | 257,099
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 396,723 | 398,329
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 638,409 | 649,224
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 516,253 | 526,274
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 185,883 | 227,053
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 46,307 | 49,076
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 601,239 | 597,664
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 0 | 0
Total investments in tax credit and other investments | 0 | 0
Derivative |  |
Derivative assets - Fair value | 277 | 323
Netting adjustments | 0 | 0
Net derivative assets | 277 | 323
Derivative liabilities - Fair value | 0 | 0
Netting adjustments | 0 | 0
Net derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 277 | 323
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Credit contracts |  |
Derivative |  |
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | $ 0 | $ 0

X
- Definition Represents the net amount of investments in the projects that qualify for Community Reinvestment Act (CRA) credits or other types of tax credits. + References No definition available. + Details
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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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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 Fair value of liability associated with 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, and obligation to return cash collateral under master netting arrangements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 5 -SubTopic 10 -Topic 815 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480463/815-10-45-5 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 55 -Paragraph 8 -SubTopic 20 -Topic 210 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-8 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 21 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-21 + Details
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- Definition Fair value, after the 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. 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