Allowance for Loans Losses - Summary of Allowance for Loans Losses (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Allowance, beginning of period	$ 4,572	$ 3,580	$ 3,580
Charge-offs	(319)		(961)
Recoveries	69		211
Net charge-offs	(250)		(750)
Provision for loan losses	575	$ 295	1,742
Allowance, end of period	4,897		4,572
Commercial and Industrial [Member]
Financing Receivable, Impaired [Line Items]
Charge-offs			(43)
Recoveries	1
Real Estate, Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Charge-offs			(4)
Recoveries			6
Consumer and Other Loans [Member]
Financing Receivable, Impaired [Line Items]
Charge-offs	(319)		(914)
Recoveries	$ 68		$ 205

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

No definition available.

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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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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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