Disclosures About Fair Value of Financial Instruments - Summary of Estimated Fair Values and Related Carrying amounts of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financial Assets
Loans held for sale	$ 55,646	$ 29,233
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets
Cash and short-term investments	60,026	15,026
Federal funds sold	480	546
Significant Observable Inputs (Level 2) [Member]
Financial Assets
Investment securities	129,359	58,688
Loans held for sale	55,646	29,233
Accrued interest receivable	2,590	1,769
Bank-owned life insurance	14,734	8,455
Financial Liabilities
Deposits	542,805	323,280
Other borrowed funds	124,971	73,113
Accrued interest payable	706	395
Significant Unobservable Inputs (Level 3) [Member]
Financial Assets
Net loans held for investment	643,878	404,888
Financial Liabilities
Deposits	168,736	81,070
Subordinated debt, net	9,874	9,766
Carrying Amount
Financial Assets
Cash and short-term investments	60,026	15,026
Federal funds sold	480	546
Investment securities	128,897	58,750
Loans held for sale	55,646	29,233
Net loans held for investment	642,262	411,288
Accrued interest receivable	2,590	1,769
Bank-owned life insurance	14,734	8,455
Financial Liabilities
Deposits	722,030	415,027
Other borrowed funds	124,800	73,100
Subordinated debt, net	9,800	9,766
Accrued interest payable	706	395
Fair Value
Financial Assets
Cash and short-term investments	60,026	15,026
Federal funds sold	480	546
Investment securities	129,359	58,688
Loans held for sale	55,646	29,233
Net loans held for investment	643,878	404,888
Accrued interest receivable	2,590	1,769
Bank-owned life insurance	14,734	8,455
Financial Liabilities
Deposits	711,541	404,350
Other borrowed funds	124,971	73,113
Subordinated debt, net	9,874	9,766
Accrued interest payable	$ 706	$ 395

Accrued interest receivable fair value disclosure.

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Bank owned life insurance fair value disclosure.

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Federal funds sold fair value disclosure.

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Loans held to maturity fair value disclosure.

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No definition available.

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Fair value portion of accrued expenses.

+ 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 210.5-02.20)
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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 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 of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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