Derivative Financial Instruments Fair Value Gains and Losses on Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Net fair value gains on derivative financial instruments	$ 831	$ (822)	$ (2,006)
Mortgage banking derivatives \| Mortgage Banking Income
Derivatives, Fair Value [Line Items]
Gain (loss) on interest rate derivative instruments	689	(748)	(1,926)
Interest Rate Swap \| Other expense
Derivatives, Fair Value [Line Items]
Gain (loss) on interest rate derivative instruments	122	1	(89)
Foreign Exchange Contracts with Correspondent Banks \| Other Income
Derivatives, Fair Value [Line Items]
Gain (loss) on foreign currency derivatives	$ 20	$ (75)	$ 9

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
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Aggregate impact of foreign currency derivatives on earnings for the period. Includes impact of foreign currency cash flow hedge ineffectiveness and the ineffectiveness of fair value hedging derivatives and full change in fair value of the foreign currency derivatives not designated as hedging instruments.

+ References

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Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

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