Loans and Allowance for Credit Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) contract	Mar. 31, 2019 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5	15
Pre-Modification Outstanding Recorded Investment	$ 685	$ 15,280
Post-Modification Outstanding Recorded Investment	$ 685	$ 15,280
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	5
Pre-Modification Outstanding Recorded Investment	$ 256	$ 1,264
Post-Modification Outstanding Recorded Investment	$ 256	$ 1,264
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	2
Pre-Modification Outstanding Recorded Investment	$ 34	$ 46
Post-Modification Outstanding Recorded Investment	$ 34	$ 46
Total Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	8
Pre-Modification Outstanding Recorded Investment	$ 395	$ 13,970
Post-Modification Outstanding Recorded Investment	$ 395	$ 13,970
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	7
Pre-Modification Outstanding Recorded Investment	$ 395	$ 13,803
Post-Modification Outstanding Recorded Investment	$ 395	$ 13,803
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 167
Post-Modification Outstanding Recorded Investment		$ 167

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

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Amount, after troubled debt restructuring, of modified financing receivable.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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