Loans and Allowance for Loan Losses - Narrative (Details)	9 Months Ended
	Sep. 30, 2019 USD ($) borrower property method component category loan numberOfQuarters relationship	Sep. 30, 2018 USD ($) loan property relationship borrower	Dec. 31, 2018 USD ($)
Financing Receivable, Impaired [Line Items]
Allowance for loan losses, number of evaluation components | component	2
Impaired loans collectively evaluated	$ 2,500,000		$ 1,700,000
Impaired loans, related reserves	$ 181,000		218,000
Number of rolling quarters | numberOfQuarters	12
Liability for unfunded commitments	$ 284,000		$ 284,000
Total valuation methods used on impaired loans | method	3
Impaired loans, identified during the period	$ 924,000
Impaired loans, principal curtailment	1,500,000
Impaired loans, partial charge-offs	676,000
Reclassification to other real estate owned	79,000
Classification to performing loans	1,400,000
Foreclosed properties held	$ 1,400,000	$ 1,700,000
Number of points in internal risk rating system | category	9
Number of categories in internal risk rating system considered as not criticized | category	6
Commercial relationship credit review threshold amount	$ 1,000,000
Past due period before loans placed in non-accrual status	90 days
Recent loan payment history before removal from non-accrual status	6 months
Commercial and Non-Residential Real Estate
Financing Receivable, Impaired [Line Items]
Foreclosure of loan relationship | relationship	2	2
Forclosure of unrelated borrower | loan	2	3
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans (as a percentage)	39.00%	42.00%
Number foreclosed properties held | property	11	8
Foreclosed properties held	$ 535,000	$ 732,000
Consumer
Financing Receivable, Impaired [Line Items]
Number of additional collateralized loans in the process of foreclosure | loan	8	2
Investment in loans in the process of foreclosure	$ 768,000	$ 1,700,000
Investment in loans in the process of foreclosure, related allowance	0	$ 88,000
Total Recorded Investment In Impaired Financing Receivables | Credit Concentration Risk
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans	$ (2,500,000)
Increase (decrease) in impaired loans (as a percentage)	(19.90%)
Commercial Loan Relationship One | Commercial and Non-Residential Real Estate
Financing Receivable, Impaired [Line Items]
Number foreclosed properties held | property	2	3
Commercial Loan Relationship One | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Foreclosed properties held	$ 294,000	$ 395,000
Commercial Loan Relationship Two | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Number foreclosed properties held | property	7	3
Foreclosed properties held	$ 163,000	$ 174,000
Commercial Loan Relationship Three | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Foreclosed properties held	$ 79,000	$ 163,000
Forclosure of unrelated borrower | borrower	2	2
Other Loan Relationships | Commercial and Non-Residential Real Estate
Financing Receivable, Impaired [Line Items]
Number foreclosed properties held | property	2
Other Loan Relationships | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans (as a percentage)	61.00%	58.00%
Number foreclosed properties held | property	2	2
Foreclosed properties held	$ 825,000	$ 1,000,000.0