Loans and Allowance for Loan Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($) contract	Jun. 30, 2018 USD ($) contract	Jun. 30, 2019 USD ($) contract	Jun. 30, 2018 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	3	7	18	24
Pre-Modification Outstanding Recorded Investment	$ 972	$ 6,552	$ 16,252	$ 69,772
Post-Modification Outstanding Recorded Investment	$ 972	$ 6,552	$ 16,252	$ 69,772
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
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	2	7	3
Pre-Modification Outstanding Recorded Investment	$ 638	$ 75	$ 1,902	$ 118
Post-Modification Outstanding Recorded Investment	$ 638	$ 75	$ 1,902	$ 118
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	1	5	9	19
Pre-Modification Outstanding Recorded Investment	$ 334	$ 6,477	$ 14,304	$ 67,868
Post-Modification Outstanding Recorded Investment	$ 334	$ 6,477	$ 14,304	$ 67,868
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	5	8	18
Pre-Modification Outstanding Recorded Investment	$ 334	$ 6,477	$ 14,137	$ 61,959
Post-Modification Outstanding Recorded Investment	$ 334	$ 6,477	$ 14,137	$ 61,959
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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No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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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