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Derivatives (Derivatives Not Designated as Hedging Instruments - Foreign Exchange Contracts) (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Derivative [Line Items] |  |
Derivative assets - Fair value | $ 330,316 | $ 107,816
Derivative liabilities - Fair Value | 256,528 | 118,305
Derivative instruments not designated as hedging instruments |  |
Derivative [Line Items] |  |
Notional amount | 20,540,031 | 15,222,341
Derivative assets - Fair value | 330,316 | 107,816
Derivative liabilities - Fair Value | 251,744 | 111,828
Derivative instruments not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 4,839,661 | 3,407,522
Derivative assets - Fair value | 54,637 | 21,624
Derivative liabilities - Fair Value | 47,024 | 19,329
Foreign exchange contracts | Customer Counterparty | Derivative instruments not designated as hedging instruments | Forwards and spot |  |
Derivative [Line Items] |  |
Notional amount | 3,581,036 | 2,023,425
Derivative assets - Fair value | 45,911 | 11,719
Derivative liabilities - Fair Value | 40,591 | 13,079
Foreign exchange contracts | Customer Counterparty | Derivative instruments not designated as hedging instruments | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 6,889 | 21,108
Derivative assets - Fair value | 16 | 348
Derivative liabilities - Fair Value | 84 | 243
Foreign exchange contracts | Customer Counterparty | Derivative instruments not designated as hedging instruments | Written options |  |
Derivative [Line Items] |  |
Notional amount | 87,036 | 537
Derivative assets - Fair value | 127 | 16
Derivative liabilities - Fair Value | 0 | 0
Foreign exchange contracts | Customer Counterparty | Derivative instruments not designated as hedging instruments | Collars |  |
Derivative [Line Items] |  |
Notional amount | 2,244 | 83,864
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair Value | 14 | 370
Foreign exchange contracts | Customer Counterparty | Derivative instruments not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 3,677,205 | 2,128,934
Derivative assets - Fair value | 46,054 | 12,083
Derivative liabilities - Fair Value | 40,689 | 13,692
Foreign exchange contracts | Financial Counterparty | Derivative instruments not designated as hedging instruments | Forwards and spot |  |
Derivative [Line Items] |  |
Notional amount | 207,492 | 506,342
Derivative assets - Fair value | 1,400 | 3,407
Derivative liabilities - Fair Value | 507 | 2,285
Foreign exchange contracts | Financial Counterparty | Derivative instruments not designated as hedging instruments | Swaps |  |
Derivative [Line Items] |  |
Notional amount | 702,391 | 687,845
Derivative assets - Fair value | 6,156 | 5,764
Derivative liabilities - Fair Value | 4,712 | 3,336
Foreign exchange contracts | Financial Counterparty | Derivative instruments not designated as hedging instruments | Purchased options |  |
Derivative [Line Items] |  |
Notional amount | 87,036 | 537
Derivative assets - Fair value | 0 | 0
Derivative liabilities - Fair Value | 127 | 16
Foreign exchange contracts | Financial Counterparty | Derivative instruments not designated as hedging instruments | Collars |  |
Derivative [Line Items] |  |
Notional amount | 165,537 | 83,864
Derivative assets - Fair value | 1,027 | 370
Derivative liabilities - Fair Value | 989 | 0
Foreign exchange contracts | Financial Counterparty | Derivative instruments not designated as hedging instruments | Foreign exchange contracts |  |
Derivative [Line Items] |  |
Notional amount | 1,162,456 | 1,278,588
Derivative assets - Fair value | 8,583 | 9,541
Derivative liabilities - Fair Value | $ 6,335 | $ 5,637

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