Borrowings - Long-term Debt (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Long-term federal home loan bank advance	$ 3,366,000	$ 3,533,000
Long-term debt outstanding	$ 60,500,000
Prime Rate \| Fixed Interest Rate Period
Debt Instrument [Line Items]
Fixed interest rate	2.12%
Long-term federal home loan bank advance	$ 3,400,000	3,500,000
Senior Long-term Debt
Debt Instrument [Line Items]
Long-term debt outstanding	$ 42,366,000
Percentage of interest used in secured pledge borrowings	85.00%
Number of shares used in secured pledge borrowings (in shares)	4,823,899
Senior Long-term Debt \| Prime Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.70%
Interest rate	(3.00%)
Long-term debt outstanding	$ 28,400,000	$ 31,700,000
Periodic principal payment	$ 812,500
Senior Long-term Debt \| Floating 3-Month LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.25%	2.50%
Interest rate	(3.00%)	(4.61%)
Long-term debt outstanding	$ 14,000,000.0	$ 16,900,000
Periodic principal payment	697,715
Junior Subordinated Debt
Debt Instrument [Line Items]
Long-term debt outstanding	$ 14,777,000
Junior Subordinated Debt \| Prime Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.75%
Interest rate	(4.00%)
Long-term debt outstanding	$ 14,800,000	$ 14,700,000
Revolving Credit Facility
Debt Instrument [Line Items]
Percentage of interest used in secured pledge borrowings	13.20%
Number of shares used in secured pledge borrowings (in shares)	735,745

The number of shares of the Company's interest in a subsidiary used as a secured pledge on a borrowing.

No definition available.

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- Definition

The percentage of the Company's interest in a subsidiary used as a secured pledge on a borrowing.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of the required periodic payments applied to principal.

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- Definition

Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

+ References

No definition available.

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- Definition

Including both current and noncurrent portions, Federal Home Loan Bank borrowings initially due beyond one year or beyond the normal operating cycle if longer.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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