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Derivative Financial Instruments (Details 2) - Non-hedging derivative financial instruments - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Derivative Financial Instruments |  |  |
Gain (loss) | $ 1,279 | $ 1,274 | $ 919
Interest rate swap contracts | Other expense |  |  |
Derivative Financial Instruments |  |  |
Gain (loss) | (650) | (252) | (30)
Interest rate swap contracts | Other income |  |  |
Derivative Financial Instruments |  |  |
Gain (loss) | 879 | 1,356 | 1,028
Loan commitments | Mortgage banking income |  |  |
Derivative Financial Instruments |  |  |
Gain (loss) | 1,302 | 73 | 46
Forward contracts - mortgage loan | Mortgage banking income |  |  |
Derivative Financial Instruments |  |  |
Gain (loss) | $ (252) | $ 97 | $ (125)

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959 + Details
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