Borrowed Funds Narrative Data (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Borrowed Funds Narrative Data [Line Items]
Option advance borrowings from the FHLB	$ 7,164,000	$ 47,200,000
FHLB borrowing capacity, loans pledged	210,000,000.0	207,700,000
FHLB borrowing capacity, maximum available	134,100,000	127,500,000
FHLB borrowings and other credit subject to collateralization	21,900,000	61,700,000
FHLB borrowing capacity, unused and available	112,200,000	65,800,000
FHLB letters of credit, collateral for deposits	23,600,000	24,800,000
FHLB letters of credit, fees paid	30,000	27,000
Union
Borrowed Funds Narrative Data [Line Items]
Correspondent banks line of credit, maximum available	15,000,000.0
Correspondent banks line of credit, amount outstanding	0	0
Company
Borrowed Funds Narrative Data [Line Items]
Correspondent banks line of credit, maximum available	5,000,000.0
Correspondent banks line of credit, amount outstanding	$ 0	$ 0
Minimum
Borrowed Funds Narrative Data [Line Items]
FHLB borrowings interest rate	0.00%	0.00%
Maximum
Borrowed Funds Narrative Data [Line Items]
FHLB borrowings interest rate	3.09%	3.09%
Weighted Average
Borrowed Funds Narrative Data [Line Items]
FHLB borrowings interest rate	3.07%	2.01%