Subordinated Debt - Additional Information (Detail) - Subordinated debt [Member] - USD ($)	1 Months Ended
May 28, 2020	Nov. 20, 2015
Subordinated Borrowing [Line Items]
Subordinated debt instrument face value	$ 15,000,000	$ 10,000,000
Subordinated debt instrument maturity date	Jun. 01, 2030	Dec. 01, 2025
Subordinated debt interest rate terms	The 2020 Note bears interest, payable on the 1st of June and December of each year, commencing December 1, 2020, at a fixed rate of 6.00% per year for the first five years, and thereafter will bear a floating interest rate of SOFR (as defined in the note) plus 587 basis points.	The 2015 Notes bear interest, payable on the 1st of June and December of each year, commencing June 1, 2016, at a fixed rate of 6.75% per year for the first five years, and thereafter will bear a floating interest rate of LIBOR plus 512.8 basis points.
Subordinated debt instrument fixed rate of interest	6.00%	6.75%
Subordinated debt instrument call feature	The Company has the right to redeem the 2020 Note, in whole or in part, without premium or penalty, at any interest payment date on or after June 1, 2025 and prior to the maturity date, but in all cases in a principal amount with integral multiples of $1,000, plus interest accrued and unpaid through the date of redemption	The Company has the right to redeem the 2015 Notes, in whole or in part, without premium or penalty, at any interest payment date on or after December 1, 2020 and prior to the maturity date, but in all cases in a principal amount with integral multiples of $1,000, plus interest accrued and unpaid through the date of redemption
Subordinated debt instrument date of first required payment	Dec. 01, 2020	Jun. 01, 2016
Subordinate debt principal amount with interest accrued	$ 1,000	$ 1,000
Subordinated debt issuance costs	$ 687,500	$ 687,500
LIBOR [Member]
Subordinated Borrowing [Line Items]
Subordinated debt instrument variable interest rate spread		512.80%
SOFR [Member]
Subordinated Borrowing [Line Items]
Subordinated debt instrument variable interest rate spread	587.00%

Principal amount with interest accrued of redemption.

No definition available.

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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

Description of a feature that permits the issuer of the debt to repay or convert it before the stated maturity date (early retirement date). The description may include such items as the call price, the period that the issuer can call the debt, including the earliest call date, and other significant terms of the call feature, which may include the debt holders' ability to convert the debt to equity if the call option is exercised and contingent events that trigger the issuer's ability to call the debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(5))
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-Section 50
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-Subparagraph (e)
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- Definition

Date the debt agreement requires the first payment to be made, in CCYY-MM-DD format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Date the payments are due on subordinated debt, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

Stated interest rate of the subordinated debt.

+ References

No definition available.

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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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