Loans and Allowance for Loan and Lease Losses (Troubled Debt Restructurings) (Details) - USD ($)	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2018	Mar. 31, 2019
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	$ 3,631,000	$ 7,741,000
Financing Receivable, Modifications, Post-Modification Recorded Investment	3,530,000	7,990,000
Financing Receivable, Modifications, Recorded Investment	2,694,000	7,020,000	$ 2,694,000
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	14,000	14,000
Financing Receivable, Modifications, Post-Modification Recorded Investment	14,000	14,000
Financing Receivable, Modifications, Recorded Investment	1,000	1,000
Commercial Portfolio [Member] \| Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment		4,110,000
Financing Receivable, Modifications, Post-Modification Recorded Investment		4,460,000
Financing Receivable, Modifications, Recorded Investment		4,302,000
Commercial Portfolio [Member] \| Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	2,940,000	2,940,000
Financing Receivable, Modifications, Post-Modification Recorded Investment	2,841,000	2,841,000
Financing Receivable, Modifications, Recorded Investment	2,184,000	2,201,000
Residential Portfolio [Member] \| Residential Mortgage [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable, Modifications, Pre-Modification Recorded Investment	677,000	677,000
Financing Receivable, Modifications, Post-Modification Recorded Investment	675,000	675,000
Financing Receivable, Modifications, Recorded Investment	$ 509,000	$ 516,000

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- Definition

Post-modification amount of investment in financing receivables 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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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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- Definition

The amount of the outstanding recorded investment related to 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 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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