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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 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Investment securities available-for-sale |  |
Available-for-sale investment securities | $ 3,016,752 | $ 3,335,795
Derivative |  |
Derivative assets | 66,146 | 83,780
Derivative liabilities | (74,935) | (82,323)
Transfer of security, from held-to-maturity, to available-for-sale | 115,600 |
U.S. Treasury securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 640,280 | 720,479
U.S. government agency and U.S. government sponsored enterprise debt securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 203,392 | 274,866
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 318,957 | 266,799
U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 1,190,271 | 1,258,747
Municipal securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 99,982 | 147,654
Non-agency residential mortgage-backed securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 9,117 | 11,477
Corporate debt securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 37,003 | 222,377
Corporate debt securities | Non-investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities |  | 9,173
Foreign bonds | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 486,408 | 383,894
Other securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 31,342 | 40,329
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 661,015 | 751,470
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign currency forward contracts |  |
Derivative |  |
Derivative assets |  | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate swaps on certificates of deposit |  |
Derivative |  |
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Interest rate swaps and options |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Credit risk participation agreements (“RPAs”) |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Warrants |  |
Derivative |  |
Derivative assets | 0 |
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | U.S. Treasury securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 640,280 | 720,479
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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Municipal securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Non-agency residential mortgage-backed securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Corporate debt securities | Non-investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities |  | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Foreign bonds | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 20,735 | 30,991
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 2,355,737 | 2,584,325
Derivative |  |
Derivative assets | 65,467 | 83,780
Derivative liabilities | (74,935) | (82,323)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign currency forward contracts |  |
Derivative |  |
Derivative assets |  | 4,325
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate swaps on certificates of deposit |  |
Derivative |  |
Derivative liabilities | (6,799) | (5,976)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Interest rate swaps and options |  |
Derivative |  |
Derivative assets | 58,633 | 67,578
Derivative liabilities | (57,958) | (65,131)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets | 5,840 | 11,874
Derivative liabilities | (10,170) | (11,213)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Credit risk participation agreements (“RPAs”) |  |
Derivative |  |
Derivative assets | 1 | 3
Derivative liabilities | (8) | (3)
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Warrants |  |
Derivative |  |
Derivative assets | 993 |
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. Treasury securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | U.S. government agency and U.S. government sponsored enterprise debt securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 203,392 | 274,866
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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 318,957 | 266,799
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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 1,190,271 | 1,258,747
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Municipal securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 99,982 | 147,654
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Non-agency residential mortgage-backed securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 9,117 | 11,477
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 37,003 | 222,377
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities | Non-investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities |  | 9,173
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Foreign bonds | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 486,408 | 383,894
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Other securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 10,607 | 9,338
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Derivative |  |
Derivative assets | 679 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign currency forward contracts |  |
Derivative |  |
Derivative assets |  | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Interest rate swaps on certificates of deposit |  |
Derivative |  |
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Interest rate swaps and options |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign exchange contracts |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Credit risk participation agreements (“RPAs”) |  |
Derivative |  |
Derivative assets | 0 | 0
Derivative liabilities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Warrants |  |
Derivative |  |
Derivative assets | 679 |
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. Treasury securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | U.S. government agency and U.S. government sponsored enterprise debt securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 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 |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Municipal securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Non-agency residential mortgage-backed securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt securities | Non-investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities |  | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Foreign bonds | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Other securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 0 | 0
Fair Value, Measurements, Recurring | Fair Value Measurements |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 3,016,752 | 3,335,795
Derivative |  |
Derivative assets | 66,146 | 83,780
Derivative liabilities | (74,935) | (82,323)
Fair Value, Measurements, Recurring | Fair Value Measurements | Foreign currency forward contracts |  |
Derivative |  |
Derivative assets |  | 4,325
Fair Value, Measurements, Recurring | Fair Value Measurements | Interest rate swaps on certificates of deposit |  |
Derivative |  |
Derivative liabilities | (6,799) | (5,976)
Fair Value, Measurements, Recurring | Fair Value Measurements | Interest rate swaps and options |  |
Derivative |  |
Derivative assets | 58,633 | 67,578
Derivative liabilities | (57,958) | (65,131)
Fair Value, Measurements, Recurring | Fair Value Measurements | Foreign exchange contracts |  |
Derivative |  |
Derivative assets | 5,840 | 11,874
Derivative liabilities | (10,170) | (11,213)
Fair Value, Measurements, Recurring | Fair Value Measurements | Credit risk participation agreements (“RPAs”) |  |
Derivative |  |
Derivative assets | 1 | 3
Derivative liabilities | (8) | (3)
Fair Value, Measurements, Recurring | Fair Value Measurements | Warrants |  |
Derivative |  |
Derivative assets | 1,672 |
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. Treasury securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 640,280 | 720,479
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise debt securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 203,392 | 274,866
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Commercial mortgage-backed securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 318,957 | 266,799
Fair Value, Measurements, Recurring | Fair Value Measurements | U.S. government agency and U.S. government sponsored enterprise mortgage-backed securities - Residential mortgage-backed securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 1,190,271 | 1,258,747
Fair Value, Measurements, Recurring | Fair Value Measurements | Municipal securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 99,982 | 147,654
Fair Value, Measurements, Recurring | Fair Value Measurements | Non-agency residential mortgage-backed securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 9,117 | 11,477
Fair Value, Measurements, Recurring | Fair Value Measurements | Corporate debt securities | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 37,003 | 222,377
Fair Value, Measurements, Recurring | Fair Value Measurements | Corporate debt securities | Non-investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities |  | 9,173
Fair Value, Measurements, Recurring | Fair Value Measurements | Foreign bonds | Investment grade |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | 486,408 | 383,894
Fair Value, Measurements, Recurring | Fair Value Measurements | Other securities |  |
Investment securities available-for-sale |  |
Available-for-sale investment securities | $ 31,342 | $ 40,329

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