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Fair Value Accounting - Financial Instruments Measured At Fair Value On A Recurring Basis (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | $ 10,918,329 | $ 7,962,438
Mutual funds and mutual funds held in rabbi trusts | 43,657 | 37,650
Derivative assets | 191,708 | 401,295
Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 779,633 | 1,218,017
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 939,623 | 1,250,377
Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 514,188 |
U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 117,838 | 20,257
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 8,012,301 | 5,000,046
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 481,744 | 370,921
Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 18,801 | 20,500
Fair Value, Measurements, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 8,391 | 10,880
Total investment securities available for sale | 10,918,329 | 7,962,438
Mortgage loans held for sale | 108,198 | 216,647
Other investments | 12,185 | 1,021
Mutual funds and mutual funds held in rabbi trusts | 43,657 | 37,650
GGL/SBA loans servicing asset | 3,233 | 3,258
Derivative assets | 191,708 | 401,295
Trading liability for short positions | 200 | 7,717
Mutual fund held in rabbi trusts | 27,205 | 20,752
Earnout liability | 0 | 5,677
Derivative liabilities | 98,602 | 157,167
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 117,838 | 20,257
Mortgage loans held for sale | 0 | 0
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 43,657 | 37,650
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 0 | 0
Trading liability for short positions | 0 | 0
Mutual fund held in rabbi trusts | 27,205 | 20,752
Earnout liability | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 8,391 | 10,880
Total investment securities available for sale | 10,800,491 | 7,940,160
Mortgage loans held for sale | 108,198 | 216,647
Other investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 191,708 | 401,295
Trading liability for short positions | 200 | 7,717
Mutual fund held in rabbi trusts | 0 | 0
Earnout liability | 0 | 0
Derivative liabilities | 95,067 | 155,119
Fair Value, Measurements, Recurring | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 2,021
Mortgage loans held for sale | 0 | 0
Other investments | 12,185 | 1,021
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 3,233 | 3,258
Derivative assets | 0 | 0
Trading liability for short positions | 0 | 0
Mutual fund held in rabbi trusts | 0 | 0
Earnout liability | 0 | 5,677
Derivative liabilities | 3,535 | 2,048
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 197 | 10,185
Total investment securities available for sale | 779,633 | 1,218,017
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 197 | 10,185
Total investment securities available for sale | 779,633 | 1,218,017
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government agencies | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 671 | 158
Total investment securities available for sale | 939,623 | 1,250,377
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 671 | 158
Total investment securities available for sale | 939,623 | 1,250,377
Fair Value, Measurements, Recurring | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Other mortgage-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 178
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 178
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Fair Value, Measurements, Recurring | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 560 | 176
Fair Value, Measurements, Recurring | State and municipal securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Fair Value, Measurements, Recurring | State and municipal securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 560 | 176
Fair Value, Measurements, Recurring | State and municipal securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Fair Value, Measurements, Recurring | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 6,963 | 183
Total investment securities available for sale | 514,188 | 0
Fair Value, Measurements, Recurring | Asset-backed securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Asset-backed securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 6,963 | 183
Total investment securities available for sale | 514,188 | 0
Fair Value, Measurements, Recurring | Asset-backed securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total trading securities | 0 | 0
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 117,838 | 20,257
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 117,838 | 20,257
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | U.S. Government agency securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 54,201 | 82,320
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 54,201 | 82,320
Fair Value, Measurements, Recurring | U.S. Government agency securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 8,012,301 | 5,000,046
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 8,012,301 | 5,000,046
Fair Value, Measurements, Recurring | Mortgage-backed securities issued by U.S. Government sponsored enterprises | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 481,744 | 370,921
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 481,744 | 370,921
Fair Value, Measurements, Recurring | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 18,801 | 20,500
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 18,801 | 18,479
Fair Value, Measurements, Recurring | Corporate debt securities and other debt securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | $ 0 | $ 2,021

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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=124258926&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=124260329&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=123581744&loc=d3e27161-111563 + Details
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