Derivative Financial Instruments (Notional and fair value amounts) (Details 1) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Interest Rate Lock Commitments
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	$ 48,677	$ 33,133
Fair Value	1,280	871
Forward Commitments
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	82,735	34,102
Fair Value	(182)	(352)
Interest Rate Swap Agreements Receive Fixed/Pay Variable Swaps
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	802,389	505,034
Fair Value	26,070	(2,537)
Interest Rate Swap Agreements Pay Fixed/Receive Variable Swaps
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	802,389	505,034
Fair Value	(4,777)	6,082
Foreign Exchange Contracts
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	85,499	55,663
Fair Value	163	793
Visa Conversion Rate Swap Agreement [Member]
Derivative Financial Instruments Not Designated as Hedging Instruments
Derivative, Notional Amount	114,499	80,746
Fair Value	$ 0	$ 0

Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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