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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, 2021 | Dec. 31, 2020
--- | --- | ---
Available-for-sale debt securities |  |
Fair Value | $ 7,789,213 | $ 5,544,658
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Total investments in tax credit and other investments | 361,438 | 266,525
Derivative |  |
Derivative assets - Fair value | 457,317 | 602,754
Net derivative assets | 349,082 | 501,242
Derivative liabilities - Fair value | 344,135 | 424,828
Net derivative liabilities | 157,448 | 240,131
U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 826,342 | 50,761
U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 1,194,005 | 814,319
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 1,169,391 | 1,153,770
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 2,247,406 | 1,660,894
Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 420,065 | 396,073
Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 281,027 | 239,842
Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 523,500 | 289,775
Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 496,643 | 405,968
Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 276,328 | 182,531
Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 63,040 | 63,231
Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 291,466 | 287,494
Fair Value, Measurements, Recurring |  |
Available-for-sale debt securities |  |
Fair Value | 7,789,213 | 5,544,658
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 26,693 | 31,272
Total investments in tax credit and other investments | 26,693 | 31,272
Derivative |  |
Derivative assets - Fair value | 457,317 | 602,754
Netting adjustments | (108,235) | (101,512)
Net derivative assets | 349,082 | 501,242
Derivative liabilities - Fair value | 344,135 | 424,828
Netting adjustments | (186,687) | (184,697)
Net derivative liabilities | 157,448 | 240,131
Fair Value, Measurements, Recurring | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 319,049 | 489,132
Derivative liabilities - Fair value | 230,290 | 317,698
Fair Value, Measurements, Recurring | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 39,562 | 30,300
Derivative liabilities - Fair value | 27,287 | 22,759
Fair Value, Measurements, Recurring | Credit contracts |  |
Derivative |  |
Derivative assets - Fair value | 5 | 13
Derivative liabilities - Fair value | 153 | 206
Fair Value, Measurements, Recurring | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 272 | 858
Fair Value, Measurements, Recurring | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 98,429 | 82,451
Derivative liabilities - Fair value | 86,405 | 84,165
Fair Value, Measurements, Recurring | U.S. Treasury securities |  |
Available-for-sale debt securities |  |
Fair Value | 826,342 | 50,761
Fair Value, Measurements, Recurring | U.S. government agency and U.S. government-sponsored enterprise debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 1,194,005 | 814,319
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 | 1,169,391 | 1,153,770
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 | 2,247,406 | 1,660,894
Fair Value, Measurements, Recurring | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 420,065 | 396,073
Fair Value, Measurements, Recurring | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 281,027 | 239,842
Fair Value, Measurements, Recurring | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 523,500 | 289,775
Fair Value, Measurements, Recurring | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 496,643 | 405,968
Fair Value, Measurements, Recurring | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 276,328 | 182,531
Fair Value, Measurements, Recurring | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 63,040 | 63,231
Fair Value, Measurements, Recurring | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 291,466 | 287,494
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Available-for-sale debt securities |  |
Fair Value | 826,342 | 50,761
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 22,233 | 22,548
Total investments in tax credit and other investments | 22,233 | 22,548
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) | Credit 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) | 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 | 826,342 | 50,761
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 | 6,962,871 | 5,493,897
Equity Securities, FV-NI and with Readily Determinable Fair Value [Abstract] |  |
Equity securities | 4,460 | 8,724
Total investments in tax credit and other investments | 4,460 | 8,724
Derivative |  |
Derivative assets - Fair value | 457,045 | 602,481
Netting adjustments | (108,235) | (101,512)
Net derivative assets | 348,810 | 500,969
Derivative liabilities - Fair value | 344,135 | 424,828
Netting adjustments | (186,687) | (184,697)
Net derivative liabilities | 157,448 | 240,131
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate contracts |  |
Derivative |  |
Derivative assets - Fair value | 319,049 | 489,132
Derivative liabilities - Fair value | 230,290 | 317,698
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets - Fair value | 39,562 | 30,300
Derivative liabilities - Fair value | 27,287 | 22,759
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Credit contracts |  |
Derivative |  |
Derivative assets - Fair value | 5 | 13
Derivative liabilities - Fair value | 153 | 206
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Equity contracts |  |
Derivative |  |
Derivative assets - Fair value | 0 | 585
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Commodity contracts |  |
Derivative |  |
Derivative assets - Fair value | 98,429 | 82,451
Derivative liabilities - Fair value | 86,405 | 84,165
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 | 1,194,005 | 814,319
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 | 1,169,391 | 1,153,770
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 | 2,247,406 | 1,660,894
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal securities |  |
Available-for-sale debt securities |  |
Fair Value | 420,065 | 396,073
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-agency commercial mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 281,027 | 239,842
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-agency residential mortgage-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 523,500 | 289,775
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities |  |
Available-for-sale debt securities |  |
Fair Value | 496,643 | 405,968
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign government bonds |  |
Available-for-sale debt securities |  |
Fair Value | 276,328 | 182,531
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Asset-backed securities |  |
Available-for-sale debt securities |  |
Fair Value | 63,040 | 63,231
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Collateralized loan obligations (“CLOs”) |  |
Available-for-sale debt securities |  |
Fair Value | 291,466 | 287,494
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 | 272 | 273
Netting adjustments | 0 | 0
Net derivative assets | 272 | 273
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) | Credit 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 | 272 | 273
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, excluding affordable housing 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 -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226003-175313 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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