Borrowings (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Total borrowings, gross	$ 63,210	$ 64,409
Unamortized discount on acquired borrowings	(2,446)	(2,580)
Total borrowings	$ 60,764	$ 61,829
Weighted average interest rate	2.14%	2.22%
FHLB Principal Reducing Credit due July 24, 2023
Debt Instrument [Line Items]
Total borrowings, gross	$ 91	$ 124
Fixed rate	1.00%	1.00%
FHLB Principal Reducing Credit due December 22, 2023
Debt Instrument [Line Items]
Total borrowings, gross	$ 962	$ 991
Fixed rate	1.25%	1.25%
FHLB Principal Reducing Credit due January 15, 2026
Debt Instrument [Line Items]
Total borrowings, gross	$ 4,500	$ 5,500
Fixed rate	1.98%	1.98%
FHLB Principal Reducing Credit due June 26, 2028
Debt Instrument [Line Items]
Total borrowings, gross	$ 227	$ 235
Fixed rate	0.25%	0.25%
FHLB Principal Reducing Credit due July 17, 2028
Debt Instrument [Line Items]
Total borrowings, gross	$ 45	$ 49
Fixed rate	0.00%	0.00%
FHLB Principal Reducing Credit due August 18, 2028
Debt Instrument [Line Items]
Total borrowings, gross	$ 168	$ 174
Fixed rate	1.00%	1.00%
FHLB Principal Reducing Credit due August 22, 2028
Debt Instrument [Line Items]
Total borrowings, gross	$ 168	$ 174
Fixed rate	1.00%	1.00%
FHLB Principal Reducing Credit due December 20, 2028
Debt Instrument [Line Items]
Total borrowings, gross	$ 345	$ 355
Fixed rate	0.50%	0.50%
FHLB Principal Reducing Credit due April 7, 2022
Debt Instrument [Line Items]
Total borrowings, gross		$ 103
Fixed rate		1.00%
Trust Preferred Securities due January 23, 2034
Debt Instrument [Line Items]
Total borrowings, gross	$ 20,620	$ 20,620
Weighted average interest rate	2.83%	2.91%
Basis spread on variable rate (as a percent)	2.70%	2.70%
Trust Preferred Securities due June 15, 2036
Debt Instrument [Line Items]
Total borrowings, gross	$ 25,774	$ 25,774
Weighted average interest rate	1.51%	1.61%
Basis spread on variable rate (as a percent)	1.39%	1.39%
Trust Preferred Securities due January 7, 2035
Debt Instrument [Line Items]
Total borrowings, gross	$ 10,310	$ 10,310
Weighted average interest rate	2.13%	2.24%
Basis spread on variable rate (as a percent)	2.00%	2.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount, after accumulated amortization, of debt discount.

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Weighted average interest rate of debt outstanding.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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