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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 | 9 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | $ 14,302 | $ 5,894 | $ 45,641 | $ 10,818
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 | 2,467 | (3,013) | 11,030 | (15,385)
Foreign exchange contracts | Foreign exchange income |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 11,820 | 5,255 | 34,035 | 14,317
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 | (20) | 26 | 175 | (72)
Equity contracts | Lending fees |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |
Net gains (losses) recognized for derivative not designated as hedging instruments | 3 | 3,592 | 388 | 11,971
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 | $ 32 | $ 34 | $ 13 | $ (13)

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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=125515794&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=125515794&loc=SL5624171-113959 + Details
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