Loans and Allowance for Loan Losses (Troubled Debt Restructurings Modified by Portfolio Class) (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract	Jun. 30, 2018 USD ($) contract	Jun. 30, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	7	40	24	53
Pre-Modification Outstanding Recorded Investment	$ 6,552	$ 59,242	$ 69,772	$ 104,334
Post-Modification Outstanding Recorded Investment	$ 6,552	$ 59,244	$ 69,772	$ 104,336
Total Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5	31
Pre-Modification Outstanding Recorded Investment	$ 6,477	$ 57,395
Post-Modification Outstanding Recorded Investment	$ 6,477	$ 57,395
Total Commercial [Member] \| Commercial Real Estate - Income Producing [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		3	1	5
Pre-Modification Outstanding Recorded Investment		$ 959	$ 1,564	$ 6,486
Post-Modification Outstanding Recorded Investment		$ 959	$ 1,564	$ 6,486
Residential Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	5	3	6
Pre-Modification Outstanding Recorded Investment	$ 75	$ 848	$ 118	$ 1,098
Post-Modification Outstanding Recorded Investment	$ 75	$ 848	$ 118	$ 1,098
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1	1	1
Pre-Modification Outstanding Recorded Investment		$ 40	$ 222	$ 40
Post-Modification Outstanding Recorded Investment		$ 42	$ 222	$ 42
Total Commercial And Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract			19	41
Pre-Modification Outstanding Recorded Investment			$ 67,868	$ 96,710
Post-Modification Outstanding Recorded Investment			$ 67,868	$ 96,710
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Non-Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	5	28	18	37
Pre-Modification Outstanding Recorded Investment	$ 6,477	$ 54,317	$ 61,959	$ 92,976
Post-Modification Outstanding Recorded Investment	$ 6,477	$ 54,317	$ 61,959	$ 92,976
Total Commercial And Industrial [Member] \| Total Commercial [Member] \| Commercial Real Estate - Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		3	1	4
Pre-Modification Outstanding Recorded Investment		$ 3,078	$ 5,909	$ 3,734
Post-Modification Outstanding Recorded Investment		$ 3,078	$ 5,909	$ 3,734

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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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