Loans and Allowance for Loan Losses (Summary of All Troubled Debt Restructuring Loans (Accruing and Non Accruing) by Portfolio Segment) (Details)	12 Months Ended
Dec. 31, 2016 USD ($) loan	Dec. 31, 2015 USD ($) loan	Dec. 31, 2014 USD ($)
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Number Of Contracts Outstanding \| loan	35	38
Financing Receivable, Modifications, Recorded Investment	$ 5,747,000	$ 5,277,000
Specific Reserve	$ 483,000	$ 603,000
Number of Contracts	6	1	6
Pre-Modification Outstanding Recorded Investment	$ 2,973,000	$ 74,000	$ 488,000
Post-Modification Outstanding Recorded Investment	2,973,000	78,000	491,000
Specific Reserve	1,400,000	27,000	49,000
Recorded investment of troubled-debt restructurings that subsequently defaulted	$ 0	$ 0	$ 0
Commercial loans
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Number Of Contracts Outstanding \| loan	10	9
Financing Receivable, Modifications, Recorded Investment	$ 1,502,000	$ 399,000
Specific Reserve	$ 0	$ 11,000
Home equity loans
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Number Of Contracts Outstanding \| loan	1	1
Financing Receivable, Modifications, Recorded Investment	$ 16,000	$ 21,000
Specific Reserve	$ 0	$ 0
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Number Of Contracts Outstanding \| loan	21	22
Financing Receivable, Modifications, Recorded Investment	$ 3,221,000	$ 3,398,000
Specific Reserve	$ 483,000	$ 544,000
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Financing Receivable Modifications Number Of Contracts Outstanding \| loan	3	6
Financing Receivable, Modifications, Recorded Investment	$ 1,008,000	$ 1,459,000
Specific Reserve	$ 0	$ 48,000
Extended Maturity [Member] \| Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 235,000
Post-Modification Outstanding Recorded Investment	0	0	235,000
Specific Reserve	$ 0	$ 0	$ 0
Extended Maturity [Member] \| Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 136,000
Post-Modification Outstanding Recorded Investment	0	0	149,000
Specific Reserve	$ 0	$ 0	$ 43,000
Extended Maturity [Member] \| Commercial loans
Financing Receivable, Modifications [Line Items]
Number of Contracts	6	0	0
Pre-Modification Outstanding Recorded Investment	$ 2,973,000	$ 0	$ 0
Post-Modification Outstanding Recorded Investment	2,973,000	0	0
Specific Reserve	$ 1,400,000	$ 0	$ 0
Court Order [Member] \| Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 74,000	$ 0
Post-Modification Outstanding Recorded Investment	0	78,000	0
Specific Reserve	$ 0	$ 27,000	$ 0
Court Order [Member] \| Commercial loans
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	3
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 77,000
Post-Modification Outstanding Recorded Investment	0	0	77,000
Specific Reserve	$ 0	$ 0	$ 6,000
Principal Forgiveness [Member] \| Home equity loans
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 40,000
Post-Modification Outstanding Recorded Investment	0	0	30,000
Specific Reserve	$ 0	$ 0	$ 0

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Allowance Related to Troubled Debt Restructuring assigned during period

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Financing Receivable Modifications Number Of Contracts Outstanding

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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