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Fair Value Accounting (Financial Instruments Measured at Fair Value on Recurring Basis) (Details) - USD ($) $ in Thousands | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | $ 7,212
Investment securities available for sale | $ 7,566,525 | 6,778,670
Mortgages Held-for-sale, Fair Value Disclosure |  | 115,173
Private equity investments |  | 19,389
GGL/SBA loans servicing asset |  | 3,040
Derivative assets |  | 140,016
Earnout liability |  | 11,016
Derivative liabilities |  | 37,071
Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 1,129,392 | 56,816
Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 354,157 | 371,592
State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 501 | 2,075
Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale |  | 327,400
U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 20,254 | 19,855
Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 4,540,386 | 5,180,815
Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 1,345,284 | 636,851
Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 19,937 | 146,725
Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 20,254 | 19,855
Private equity investments | 0 | 15,502
Mutual funds and mutual funds held in rabbi trusts | 35,174 | 32,348
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 0 | 0
Trading liability for short positions |  | 1,560
Earnout liability | 0 | 0
Derivative liabilities | 0 | 0
Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 4,371 | 7,212
Investment securities available for sale | 7,544,471 | 6,756,710
Mortgages Held-for-sale, Fair Value Disclosure | 285,899 |
Private equity investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 463,028 | 140,016
Trading liability for short positions |  | 0
Earnout liability | 0 | 0
Derivative liabilities | 178,508 | 34,732
Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 1,800 | 2,105
Private equity investments | 958 | 3,887
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 3,100 | 3,040
Derivative assets | 0 | 0
Trading liability for short positions |  | 0
Earnout liability | 15,924 | 11,016
Derivative liabilities | 1,460 | 2,339
Fair Value, Measurements, Recurring Basis |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 4,371 |
Mortgages Held-for-sale, Fair Value Disclosure | 285,899 |
Private equity investments | 958 |
Mutual funds and mutual funds held in rabbi trusts | 35,174 | 32,348
GGL/SBA loans servicing asset | 3,100 |
Derivative assets | 463,028 |
Trading liability for short positions |  | 1,560
Earnout liability | 15,924 |
Derivative liabilities | 179,968 |
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 18 |
Investment securities available for sale | 1,129,392 | 56,816
Fair Value, Measurements, Recurring Basis | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 604 | 2,486
Investment securities available for sale | 354,157 | 371,592
Fair Value, Measurements, Recurring Basis | Other mortgage-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 673 | 1,284
Fair Value, Measurements, Recurring Basis | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 579 | 65
Investment securities available for sale | 501 | 2,075
Fair Value, Measurements, Recurring Basis | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 2,497 | 3,227
Investment securities available for sale |  | 327,400
Fair Value, Measurements, Recurring Basis | Other investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 150
Fair Value, Measurements, Recurring Basis | U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 20,254 | 19,855
Fair Value, Measurements, Recurring Basis | U.S. Government agency securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 156,614 | 36,541
Fair Value, Measurements, Recurring Basis | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 4,540,386 | 5,180,815
Fair Value, Measurements, Recurring Basis | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 1,345,284 | 636,851
Fair Value, Measurements, Recurring Basis | Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 19,937 | 146,725
Fair Value, Measurements, Recurring Basis | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 |
Mortgages Held-for-sale, Fair Value Disclosure | 0 | 0
Private equity investments | 0 | 15,502
Mutual funds and mutual funds held in rabbi trusts | 35,174 | 32,348
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 0 |
Trading liability for short positions |  | 1,560
Earnout liability | 0 | 0
Derivative liabilities | 0 |
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other mortgage-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale |  | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Other investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 0
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 20,254 |
Fair Value, Measurements, Recurring Basis | Level 1 | U.S. Government agency securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 1 | Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 4,371 |
Mortgages Held-for-sale, Fair Value Disclosure | 285,899 | 115,173
Private equity investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 0 | 0
Derivative assets | 463,028 |
Trading liability for short positions |  | 0
Earnout liability | 0 | 0
Derivative liabilities | 178,508 |
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 18 |
Investment securities available for sale | 1,129,392 | 56,816
Fair Value, Measurements, Recurring Basis | Level 2 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 2,486
Investment securities available for sale | 354,157 | 371,592
Fair Value, Measurements, Recurring Basis | Level 2 | Other mortgage-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 673 | 1,284
Fair Value, Measurements, Recurring Basis | Level 2 | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 579 | 65
Investment securities available for sale | 501 | 2,075
Fair Value, Measurements, Recurring Basis | Level 2 | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 2,497 | 3,227
Investment securities available for sale |  | 327,400
Fair Value, Measurements, Recurring Basis | Level 2 | Other investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 150
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 2 | U.S. Government agency securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 156,614 | 36,541
Fair Value, Measurements, Recurring Basis | Level 2 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 4,540,386 | 5,180,815
Fair Value, Measurements, Recurring Basis | Level 2 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 604 |
Investment securities available for sale | 1,345,284 | 636,851
Fair Value, Measurements, Recurring Basis | Level 2 | Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 18,137 | 144,620
Fair Value, Measurements, Recurring Basis | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 |
Investment securities available for sale | 1,800 | 2,105
Mortgages Held-for-sale, Fair Value Disclosure | 0 | 0
Private equity investments | 958 | 3,887
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 3,100 | 3,040
Derivative assets | 0 |
Trading liability for short positions |  | 0
Earnout liability | 15,924 | 11,016
Derivative liabilities | 1,460 |
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Commercial mortgage-backed securities issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other mortgage-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Investment securities available for sale |  | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Other investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | U.S. Government agency securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Mortgage-backed securities issued by U.S. Government sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Collateralized mortgage obligations issued by U.S. Government agencies or sponsored enterprises |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | 0 | 0
Fair Value, Measurements, Recurring Basis | Level 3 | Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment securities available for sale | $ 1,800 | $ 2,105

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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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