Derivative Financial Instruments (Notional Amounts) (Details 1) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Interest Rate Lock Commitments
Derivative [Line Items]
Notional Amount	$ 25,566	$ 35,422
Fair Value	425	789
Forward Commitments
Derivative [Line Items]
Notional Amount	34,134	45,143
Fair Value	144	(56)
Receive Fixed / Pay Variable Swap
Derivative [Line Items]
Notional Amount	472,280	374,670
Fair Value	(13,953)	(1,331)
Pay Fixed / Receive Variable Swap
Derivative [Line Items]
Notional Amount	472,280	374,670
Fair Value	13,344	1,436
Foreign Exchange Contracts
Derivative [Line Items]
Notional Amount	55,382	54,332
Fair Value	(676)	(13)
Visa Conversion Rate Swap Agreement
Derivative [Line Items]
Notional Amount	91,854	70,571
Fair Value	$ 0	$ 0

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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- Definition

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

+ References

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=109250915&loc=d3e13433-108611

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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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