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Fair Value Accounting (Financial Instruments Measured At Fair Value On A Recurring Basis) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | $ 7,962,438 | $ 6,778,670
Private equity investments | 1,021 | 19,389
Mutual funds and mutual funds held in rabbi trusts | 37,650 | 32,348
Derivative asset positions | 401,295 | 140,016
Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale | 20,257 | 19,855
Private equity investments | 0 | 15,502
Mutual funds and mutual funds held in rabbi trusts | 37,650 | 32,348
GGL/SBA loans servicing asset | 0 | 0
Derivative asset positions | 0 | 0
Trading liability for short positions | 0 | 1,560
Earnout liability | 0 | 0
Derivative liabilities | 0 | 0
Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 10,880 | 7,212
Total investment securities available for sale | 7,940,160 | 6,756,710
Private equity investments | 0 | 0
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 0 | 0
Derivative asset positions | 401,295 | 140,016
Trading liability for short positions | 7,717 | 0
Earnout liability | 0 | 0
Derivative liabilities | 155,119 | 34,732
Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale | 2,021 | 2,105
Private equity investments | 1,021 | 3,887
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
GGL/SBA loans servicing asset | 3,258 | 3,040
Derivative asset positions | 0 | 0
Trading liability for short positions | 0 | 0
Earnout liability | 5,677 | 11,016
Derivative liabilities | 2,048 | 2,339
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 | 1,250,377 | 636,851
State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale |  | 2,075
Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale |  | 327,400
U.S. Treasury securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 20,257 | 19,855
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 | 1,218,017 | 56,816
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 | 5,000,046 | 5,180,815
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 | 370,921 | 371,592
Corporate debt securities and other debt securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Total investment securities available for sale | 20,500 | 146,725
Fair Value, Measurements, Recurring |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 10,880 | 7,212
Total investment securities available for sale | 7,962,438 | 6,778,670
Mortgage loans held for sale | 216,647 | 115,173
Private equity investments | 1,021 | 19,389
GGL/SBA loans servicing asset | 3,258 | 3,040
Derivative asset positions | 401,295 | 140,016
Trading liability for short positions | 7,717 | 1,560
Earnout liability | 5,677 | 11,016
Derivative liabilities | 157,167 | 37,071
Fair Value, Measurements, Recurring | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale | 20,257 | 19,855
Mortgage loans held for sale | 0 | 0
Private equity investments | 0 | 15,502
GGL/SBA loans servicing asset | 0 | 0
Derivative asset positions | 0 | 0
Trading liability for short positions | 0 | 1,560
Earnout liability | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 10,880 | 7,212
Total investment securities available for sale | 7,940,160 | 6,756,710
Mortgage loans held for sale | 216,647 | 115,173
Private equity investments | 0 | 0
GGL/SBA loans servicing asset | 0 | 0
Derivative asset positions | 401,295 | 140,016
Trading liability for short positions | 7,717 | 0
Earnout liability | 0 | 0
Derivative liabilities | 155,119 | 34,732
Fair Value, Measurements, Recurring | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale | 2,021 | 2,105
Mortgage loans held for sale | 0 | 0
Private equity investments | 1,021 | 3,887
GGL/SBA loans servicing asset | 3,258 | 3,040
Derivative asset positions | 0 | 0
Trading liability for short positions | 0 | 0
Earnout liability | 5,677 | 11,016
Derivative liabilities | 2,048 | 2,339
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] |  |
Trading securities | 158 |
Total investment securities available for sale | 1,250,377 | 636,851
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] |  |
Trading securities | 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] |  |
Trading securities | 158 |
Total investment securities available for sale | 1,250,377 | 636,851
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] |  |
Trading securities | 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] |  |
Trading securities | 178 | 1,284
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 178 | 1,284
Fair Value, Measurements, Recurring | Other mortgage-backed securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Fair Value, Measurements, Recurring | State and municipal securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 176 | 65
Total investment securities available for sale |  | 2,075
Fair Value, Measurements, Recurring | State and municipal securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale |  | 0
Fair Value, Measurements, Recurring | State and municipal securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 176 | 65
Total investment securities available for sale |  | 2,075
Fair Value, Measurements, Recurring | State and municipal securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale |  | 0
Fair Value, Measurements, Recurring | Asset-backed securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 183 | 3,227
Total investment securities available for sale |  | 327,400
Fair Value, Measurements, Recurring | Asset-backed securities | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale |  | 0
Fair Value, Measurements, Recurring | Asset-backed securities | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 183 | 3,227
Total investment securities available for sale |  | 327,400
Fair Value, Measurements, Recurring | Asset-backed securities | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 0 | 0
Total investment securities available for sale |  | 0
Fair Value, Measurements, Recurring | Other investments |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 150
Fair Value, Measurements, Recurring | Other investments | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 0
Fair Value, Measurements, Recurring | Other investments | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 150
Fair Value, Measurements, Recurring | Other investments | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities |  | 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 | 20,257 | 19,855
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 | 20,257 | 19,855
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 | 82,320 | 36,541
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 | 82,320 | 36,541
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 agencies |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Trading securities | 10,185 |
Total investment securities available for sale | 1,218,017 | 56,816
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] |  |
Trading securities | 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] |  |
Trading securities | 10,185 |
Total investment securities available for sale | 1,218,017 | 56,816
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] |  |
Trading securities | 0 |
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 | 5,000,046 | 5,180,815
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 | 5,000,046 | 5,180,815
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] |  |
Trading securities |  | 2,486
Total investment securities available for sale | 370,921 | 371,592
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] |  |
Trading securities |  | 0
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] |  |
Trading securities |  | 2,486
Total investment securities available for sale | 370,921 | 371,592
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] |  |
Trading securities |  | 0
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 | 20,500 | 146,725
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 | 18,479 | 144,620
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 | 2,021 | 2,105
Fair Value, Measurements, Recurring | Mutual funds |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Mutual funds and mutual funds held in rabbi trusts | 37,650 | 32,348
Fair Value, Measurements, Recurring | Mutual funds | Level 1 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Mutual funds and mutual funds held in rabbi trusts | 37,650 | 32,348
Fair Value, Measurements, Recurring | Mutual funds | Level 2 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Mutual funds and mutual funds held in rabbi trusts | 0 | 0
Fair Value, Measurements, Recurring | Mutual funds | Level 3 |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Mutual funds and mutual funds held in rabbi trusts | $ 0 | $ 0

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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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