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, 2019 USD ($) loan	Dec. 31, 2018 USD ($) loan	Dec. 31, 2017 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	27	31
Recorded Investment	$ 3,629,000	$ 4,406,000
Specific Reserve	$ 463,000	$ 628,000
Number of Contracts	2	3	5
Pre-Modification Outstanding Recorded Investment	$ 64,000	$ 397,000	$ 895,000
Post-Modification Outstanding Recorded Investment	69,000	420,000	914,000
Specific Reserve	$ 15,000	$ 95,000	$ 45,000
Commercial real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	2	2
Recorded Investment	$ 338,000	$ 347,000
Specific Reserve	$ 30,000	$ 23,000
Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	2	2
Recorded Investment	$ 123,000	$ 141,000
Specific Reserve	$ 0	$ 0
Home equity
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	1	2
Recorded Investment	$ 299,000	$ 304,000
Specific Reserve	$ 69,000	$ 162,000
Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	22	25
Recorded Investment	$ 2,869,000	$ 3,614,000
Specific Reserve	$ 364,000	443,000
Home Equity Loan
Financing Receivable, Modifications [Line Items]
Specific Reserve		$ 162,000
Maturity Concession \| Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts	0	0	2
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 298,000
Post-Modification Outstanding Recorded Investment	0	0	298,000
Specific Reserve	$ 0	$ 0	$ 15,000
Interest Rate Concession \| Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 134,000
Post-Modification Outstanding Recorded Investment	0	0	145,000
Specific Reserve	$ 0	$ 0	$ 0
Interest Rate and Maturity Concession \| Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	2	2	1
Pre-Modification Outstanding Recorded Investment	$ 64,000	$ 231,000	$ 148,000
Post-Modification Outstanding Recorded Investment	69,000	254,000	156,000
Specific Reserve	$ 15,000	$ 50,000	$ 30,000
Interest Rate and Maturity Concession \| Home Equity Loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	0	0	1
Pre-Modification Outstanding Recorded Investment	$ 0	$ 0	$ 315,000
Post-Modification Outstanding Recorded Investment	0	0	315,000
Specific Reserve	$ 0	$ 0	$ 0
Payment Deferral \| Residential real estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	0	1	0
Pre-Modification Outstanding Recorded Investment	$ 0	$ 166,000	$ 0
Post-Modification Outstanding Recorded Investment	0	166,000	0
Specific Reserve	$ 0	$ 45,000	$ 0

Allowance for Credit Losses, Related to Troubled Debt Restructured Loans

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Allowance Related to Troubled Debt Restructurings assigned during period

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Financing Receivable Modifications Number Of Contracts Outstanding

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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
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-Topic 310
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 40
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-Paragraph 4
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