Borrowings (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Debt Instrument [Line Items]
Long-term debt outstanding	$ 71,723,000	$ 66,296,000	$ 82,407,000
FHLB Advances
Debt Instrument [Line Items]
Long-term debt outstanding	$ 55,716,000	58,716,000
Weighted average rate percentage	2.21%
Trust preferred subordinated debt
Debt Instrument [Line Items]
Interest rate percentage	6.39%
Loan payable to local bank, 4.5% | Loan payable to local bank
Debt Instrument [Line Items]
Long-term debt outstanding	$ 1,707,000	1,830,000
Interest rate percentage	4.50%
Period of fixed interest rate	5 years
Loan payable to local bank, 5.25% | Loan payable to local bank
Debt Instrument [Line Items]
Long-term debt outstanding	$ 600,000	750,000
Loan payable to local bank, 5.25% | Loan payable to local bank | Wall Street Journal Prime Rate
Debt Instrument [Line Items]
Basis spread on prime rate, percentage	0.25%
Effective rate, percentage	4.00%
Trust preferred subordinated debt, NWSB | Trust preferred subordinated debt
Debt Instrument [Line Items]
Long-term debt outstanding	$ 5,000,000	5,000,000
Trust preferred subordinated debt issued	5,000,000
Trust preferred subordinated debt, FCBI | Trust preferred subordinated debt
Debt Instrument [Line Items]
Long-term debt outstanding	6,000,000	$ 0
Trust preferred subordinated debt issued	$ 6,000,000