Loans and Allowance for Loan Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2018 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	13	26	31	50
Pre-Modification Outstanding Recorded Investment	$ 13,896	$ 24,595	$ 30,148	$ 94,367
Post-Modification Outstanding Recorded Investment	$ 7,084	$ 24,595	$ 23,336	$ 94,367
Total Commercial [Member] \| Commercial Real Estate - Income Producing [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1		1	1
Pre-Modification Outstanding Recorded Investment	$ 123		$ 123	$ 1,564
Post-Modification Outstanding Recorded Investment	$ 123		$ 123	$ 1,564
Total Commercial [Member] \| Construction and Land Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3		3
Pre-Modification Outstanding Recorded Investment	$ 323		$ 323
Post-Modification Outstanding Recorded Investment	$ 323		$ 323
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	8	10	11
Pre-Modification Outstanding Recorded Investment	$ 297	$ 930	$ 2,199	$ 1,048
Post-Modification Outstanding Recorded Investment	$ 297	$ 930	$ 2,199	$ 1,048
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	4	6	6	7
Pre-Modification Outstanding Recorded Investment	$ 70	$ 89	$ 116	$ 311
Post-Modification Outstanding Recorded Investment	$ 70	$ 89	$ 116	$ 311
Total Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	12	11	31
Pre-Modification Outstanding Recorded Investment	$ 13,083	$ 23,576	$ 27,387	$ 91,444
Post-Modification Outstanding Recorded Investment	$ 6,271	$ 23,576	$ 20,575	$ 91,444
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	11	10	29
Pre-Modification Outstanding Recorded Investment	$ 13,083	$ 23,347	$ 27,220	$ 85,306
Post-Modification Outstanding Recorded Investment	$ 6,271	$ 23,347	$ 20,408	$ 85,306
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1	1	2
Pre-Modification Outstanding Recorded Investment		$ 229	$ 167	$ 6,138
Post-Modification Outstanding Recorded Investment		$ 229	$ 167	$ 6,138

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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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