Fair Value Measurements and Disclosures - Schedule of Carrying Amounts and Estimated Fair Values of Company's Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financial assets:
Investment securities available-for-sale	$ 44,071	$ 24,005
Carrying Amount
Financial assets:
Cash and cash equivalents	130,910	178,253
Investment securities available-for-sale	44,071	24,005
Other investments	2,476	1,596
Loans, net	563,539	592,254
Cash surrender value of life insurance	15,285	15,311
Financial liabilities:
Deposits	615,231	640,165
FHLB advances	49,020	19,117
PPPLF borrowings		100,813
Other borrowings		5,000
Estimated Fair Value
Financial assets:
Cash and cash equivalents	130,910	178,253
Investment securities available-for-sale	44,071	24,005
Other investments	2,476	1,596
Loans, net	573,930	611,625
Cash surrender value of life insurance	15,285	15,311
Financial liabilities:
Deposits	606,610	639,269
FHLB advances	$ 47,694	16,769
PPPLF borrowings		100,813
Other borrowings		$ 5,000

Other borrowings fair value disclosure.

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Payroll protection program loans fair value disclosure.

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Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 6A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=SL6742756-110258

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Fair value portion of borrowing from Federal Home Loan Bank (FHLBank).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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