Loans and Allowance for Loan Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) contract	Dec. 31, 2017 USD ($) contract	Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	56	78	47
Pre-Modification Outstanding Recorded Investment	$ 94,760	$ 177,070	$ 132,234
Post-Modification Outstanding Recorded Investment	$ 94,760	$ 177,070	$ 132,234
Total Commercial [Member] \| Commercial Real Estate - Income Producing [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	5	1
Pre-Modification Outstanding Recorded Investment	$ 1,564	$ 5,625	$ 2,943
Post-Modification Outstanding Recorded Investment	$ 1,564	$ 5,625	$ 2,943
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	14	15	7
Pre-Modification Outstanding Recorded Investment	$ 1,297	$ 2,812	$ 694
Post-Modification Outstanding Recorded Investment	$ 1,297	$ 2,812	$ 694
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	10	1
Pre-Modification Outstanding Recorded Investment	$ 455	$ 40
Post-Modification Outstanding Recorded Investment	$ 455	$ 40
Total Commercial And Industrial [Member] \| Total Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	31	57	39
Pre-Modification Outstanding Recorded Investment	$ 91,444	$ 168,593	$ 128,597
Post-Modification Outstanding Recorded Investment	$ 91,444	$ 168,593	$ 128,597
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	29	52	38
Pre-Modification Outstanding Recorded Investment	$ 85,306	$ 162,909	$ 128,449
Post-Modification Outstanding Recorded Investment	$ 85,306	$ 162,909	$ 128,449
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	5	1
Pre-Modification Outstanding Recorded Investment	$ 6,138	$ 5,684	$ 148
Post-Modification Outstanding Recorded Investment	$ 6,138	$ 5,684	$ 148

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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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