Loans and Allowance for Loan Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) contract	Mar. 31, 2018 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	15	17
Pre-Modification Outstanding Recorded Investment	$ 15,280	$ 63,220
Post-Modification Outstanding Recorded Investment	$ 15,280	$ 63,220
Total Commercial [Member] \| Commercial Real Estate - Income Producing [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 1,564
Post-Modification Outstanding Recorded Investment		$ 1,564
Total Commercial [Member] \| Construction and Land Development [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Pre-Modification Outstanding Recorded Investment		$ 43
Post-Modification Outstanding Recorded Investment		$ 43
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5
Pre-Modification Outstanding Recorded Investment	$ 1,264
Post-Modification Outstanding Recorded Investment	$ 1,264
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	1
Pre-Modification Outstanding Recorded Investment	$ 46	$ 222
Post-Modification Outstanding Recorded Investment	$ 46	$ 222
Total Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	8	14
Pre-Modification Outstanding Recorded Investment	$ 13,970	$ 61,391
Post-Modification Outstanding Recorded Investment	$ 13,970	$ 61,391
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	7	13
Pre-Modification Outstanding Recorded Investment	$ 13,803	$ 55,482
Post-Modification Outstanding Recorded Investment	$ 13,803	$ 55,482
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
Pre-Modification Outstanding Recorded Investment	$ 167	$ 5,909
Post-Modification Outstanding Recorded Investment	$ 167	$ 5,909

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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