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Derivatives (Net Gains (Losses) on Derivatives Not Designated as Hedging Instruments) (Details) - Derivatives not designated as hedging instruments - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2021 | Mar. 31, 2020
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | $ 24,669 | $ (3,840)
Interest rate contracts | Interest rate contracts and other derivative income |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 13,901 | (7,011)
Foreign exchange contracts | Foreign exchange income |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 10,243 | 2,861
Credit contracts | Interest rate contracts and other derivative income |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 45 | (23)
Equity contracts | Lending fees |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 311 | 309
Commodity contracts | Interest rate contracts and other derivative income |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | $ 169 | $ 24

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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/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + Details
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