Disclosures About Fair Value of Financial Instruments - Summary of Estimated Fair Values and Related Carrying amounts of Financial Instruments (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Financial Assets
Loans held for sale	$ 127,796	$ 55,646
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Assets
Cash and short-term investments	241,136	60,026
Federal funds sold	452	480
Significant Observable Inputs (Level 2) [Member]
Financial Assets
Investment securities	114,003	129,359
Loans held for sale	127,796	55,646
Accrued interest receivable	4,119	2,590
Bank-owned life insurance	14,919	14,734
Financial Liabilities
Deposits	690,229	542,805
Other borrowed funds	476,750	124,971
Accrued interest payable	678	706
Significant Unobservable Inputs (Level 3) [Member]
Financial Assets
Net loans held for investment	1,013,388	643,878
Financial Liabilities
Deposits	283,368	168,736
Subordinated debt, net	24,472	9,784
Carrying Amount
Financial Assets
Cash and short-term investments	241,136	60,026
Federal funds sold	452	480
Investment securities	114,003	128,897
Loans held for sale	127,796	55,646
Net loans held for investment	1,013,259	642,262
Accrued interest receivable	4,119	2,590
Bank-owned life insurance	14,919	14,734
Financial Liabilities
Deposits	965,857	722,030
Other borrowed funds	478,411	124,800
Subordinated debt, net	24,472	9,800
Accrued interest payable	678	706
Fair Value
Financial Assets
Cash and short-term investments	241,136	60,026
Federal funds sold	452	480
Investment securities	114,003	129,359
Loans held for sale	127,796	55,646
Net loans held for investment	1,013,388	643,878
Accrued interest receivable	4,119	2,590
Bank-owned life insurance	14,919	14,734
Financial Liabilities
Deposits	973,597	711,541
Other borrowed funds	476,750	124,971
Subordinated debt, net	24,472	9,784
Accrued interest payable	$ 678	$ 706

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
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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-Publisher FASB
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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=120398452&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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