Commitments and Contingencies (Details)	12 Months Ended
	Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($) item
Financial instruments whose contract amount represents credit risk [Abstract]
Deposits	$ 661,049,000	$ 779,506,000
Interest income	30,507,000	29,057,000
Noninterest Income	10,264,000	8,429,000
Standby Letters of Credit [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	$ 3,325,000	3,321,000
Letters of credit expiry period	12 months
Current liability for guarantees	$ 14,000	42,000
Home Equity Lines of Credit [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	$ 16,917,000	17,015,000
Loan expiry period	10 years
Unadvanced Construction Commitments [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	$ 79,378,000	75,326,000
Mortgage Loan Commitments [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	$ 701,000	$ 1,649,000
Number of mortgage loan commitments at fixed interest rate | item	3	3
Residential mortgage loan commitments	$ 701,000,000,000	$ 1,600,000
Lines of Credit [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	16,501,000	20,990,000
Loans Sold and Serviced with Limited Repurchase Provisions [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Off-balance sheet credit risk	76,536,000	49,623,000
Repurchases of loans previously sold	$ 0	0
Loans Sold and Serviced with Limited Repurchase Provisions [Member] | Minimum [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Period of delinquency under repurchase agreement	120 days
Loans Sold and Serviced with Limited Repurchase Provisions [Member] | Maximum [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Period of delinquency under repurchase agreement	180 days
Business activities with medical-use cannabis customers [Member] | Cannabis Customers [Member]
Financial instruments whose contract amount represents credit risk [Abstract]
Deposits	$ 22,800,000	17,000,000
Loan balances	$ 14,000,000	$ 14,100,000
Percentage of deposits in total deposits	3.40%	2.20%
Percentage of loans in total loans	2.20%	2.10%
Interest income	$ 773,000	$ 720,000
Noninterest Income	2,000,000	1,400,000
Volume of deposits accepted	$ 267,600,000	$ 138,900,000