Loans and Allowance for Loan Losses - Narrative (Details)	3 Months Ended
	Mar. 31, 2020 USD ($) property component loan relationship method category borrower quarter	Mar. 31, 2019 USD ($) property loan borrower relationship	Dec. 31, 2019 USD ($)
Financing Receivable, Impaired [Line Items]
Allowance for loan losses, number of evaluation components | component	2
Impaired loans collectively evaluated	$ 2,400,000		$ 2,000,000.0
Impaired loans, related reserves	$ 77,000		139,000
Number of rolling quarters | quarter	12
Liability for unfunded commitments	$ 332,000		$ 332,000
Total valuation methods used on impaired loans | method	3
Impaired loans, identified during the period	$ 980,000
Impaired loans, curtailment	$ 64,000
Foreclosure of loan relationship | loan	1
Reclassification to other real estate owned	$ 23,000
Classification to performing loans	6,000
Normal loan amortization	145,000
Foreclosed properties held	$ 1,200,000	$ 2,100,000
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	1	2
Foreclosure of unrelated borrower | loan	2	3
Residential Real Estate
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans (as a percentage)	32.00%	42.00%
Number foreclosed properties held | property	4	12
Foreclosed properties held	$ 380,000	$ 877,000
Consumer
Financing Receivable, Impaired [Line Items]
Number of additional collateralized loans in the process of foreclosure | loan	4	3
Investment in loans in the process of foreclosure	$ 214,000	$ 270,000
Investment in loans in the process of foreclosure, related allowance	0	$ 0
Total Recorded Investment In Impaired Financing Receivables | Credit Concentration Risk
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans	$ 743,000
Increase (decrease) in impaired loans (as a percentage)	7.80%
Commercial Loan Relationship One | Commercial and Non-Residential Real Estate
Financing Receivable, Impaired [Line Items]
Number foreclosed properties held | property	2	2
Commercial Loan Relationship One | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Foreclosed properties held	$ 294,000	$ 294,000
Commercial Loan Relationship Two | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Number foreclosed properties held | property		7
Foreclosed properties held		$ 174,000
Commercial Loan Relationship Three | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Foreclosed properties held	$ 86,000	$ 409,000
Foreclosure of unrelated borrower | borrower	2	3
Other Loan Relationships | Residential Real Estate
Financing Receivable, Impaired [Line Items]
Increase (decrease) in impaired loans (as a percentage)	68.00%	58.00%
Number foreclosed properties held | property	2	3
Foreclosed properties held	$ 826,000	$ 1,200,000