Loans and Allowance for Loan Losses - Summary of Allowance for Loans Losses (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Allowance, beginning of period	$ 3,580	$ 2,802
Charge-offs	(961)	(563)
Recoveries	211	116
Net charge-offs (recoveries)	(750)	(447)
Provision for loan losses	1,742	1,225
Allowance, end of period	4,572	3,580
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Allowance, beginning of period	572	494
Charge-offs	(43)	(5)
Provision for loan losses	312	83
Allowance, end of period	841	572
Real Estate, Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Charge-offs	(4)	(13)
Recoveries	6	12
Consumer and Other Loans [Member]
Financing Receivable, Impaired [Line Items]
Charge-offs	(914)	(545)
Recoveries	$ 205	$ 104

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount, after recoveries, of loans and leases that have been written-off.

+ References

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No definition available.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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