Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1,439	$ 1,206
Share-based compensation arrangement by share-based payment award, options, outstanding, number (in shares)	0	0
Options granted (in shares)	0	0
Options exercised (in shares)	0	1,757
Share-based compensation arrangement by share-based payment award, options, exercises in period, intrinsic value		$ 13
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	17,722
Granted (in usd per share)	$ 19.74
Share-based compensation expense	$ 87	$ 88
Restricted Stock \| 2018 Omnibus Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 262
Unrecognized compensation expense, period of recognition	9 months 18 days
Restricted Stock \| 2018 Omnibus Equity Incentive Plan \| Non-Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	17,722	16,035
Granted (in usd per share)	$ 19.74	$ 13.72
Vesting period	1 year	1 year
Share-based compensation expense	$ 350	$ 220
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	298,554
Granted (in usd per share)	$ 18.07
Share-based compensation expense	$ 1,400	$ 1,100
Unrecognized compensation cost	$ 9,000
Unrecognized compensation expense, period of recognition	1 year 8 months 23 days
RSUs \| 2018 Omnibus Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	298,554	258,154
Granted (in usd per share)	$ 18.07	$ 16.22
Vesting period	3 years	3 years
Share-based compensation expense	$ 1,800	$ 1,400
RSUs \| 2018 Omnibus Equity Incentive Plan \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
RSUs \| 2018 Omnibus Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years

Average annual compensation cost over vesting period.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Number of share options (or share units) exercised during the current period.

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