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Derivatives (Net Gains (Losses) on Derivatives Not Designated as Hedging Instruments) (Details) - Derivative instruments not designated as hedging instruments - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | $ 21,969 | $ 15,189 | $ 4,400
Interest rate swaps and options | Derivative fees and other income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | (1,772) | 2,557 | 65
Foreign exchange contracts | Foreign exchange income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | 22,076 | 12,632 | 4,235
Foreign exchange options | Foreign exchange income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | 0 | 0 | 236
Credit risk participation agreements (“RPAs”) | Derivative fees and other income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | (7) | 0 | 0
Warrants | Ancillary loan fees and other income |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | 1,672 | 0 | 0
Embedded derivative liabilities | Other operating expense |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Total net income (loss) | $ 0 | $ 0 | $ (136)

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- Definition Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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