Loans and Allowance for Credit Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	7	13	25	31
Pre-Modification Outstanding Recorded Investment	$ 1,383	$ 13,896	$ 4,273	$ 30,148
Post-Modification Outstanding Recorded Investment	$ 1,383	$ 7,084	$ 4,273	$ 23,336
Total Commercial [Member] \| Commercial Real Estate - Income Producing [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1		1
Pre-Modification Outstanding Recorded Investment		$ 123		$ 123
Post-Modification Outstanding Recorded Investment		$ 123		$ 123
Total Commercial [Member] \| Construction and Land Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		3	1	3
Pre-Modification Outstanding Recorded Investment		$ 323	$ 15	$ 323
Post-Modification Outstanding Recorded Investment		$ 323	$ 15	$ 323
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5	3	14	10
Pre-Modification Outstanding Recorded Investment	$ 1,358	$ 297	$ 3,424	$ 2,199
Post-Modification Outstanding Recorded Investment	$ 1,358	$ 297	$ 3,424	$ 2,199
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	4	7	6
Pre-Modification Outstanding Recorded Investment	$ 25	$ 70	$ 89	$ 116
Post-Modification Outstanding Recorded Investment	$ 25	$ 70	$ 89	$ 116
Total Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		2	3	11
Pre-Modification Outstanding Recorded Investment		$ 13,083	$ 745	$ 27,387
Post-Modification Outstanding Recorded Investment		$ 6,271	$ 745	$ 20,575
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		2	3	10
Pre-Modification Outstanding Recorded Investment		$ 13,083	$ 745	$ 27,220
Post-Modification Outstanding Recorded Investment		$ 6,271	$ 745	$ 20,408
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=121611835&loc=SL6953676-111524

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