Equity Incentive Plan - Summary of Company's Outstanding Restricted Stock (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) $ / shares shares
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	76,530
Expected future remaining compensation expense \| $	$ 1,432
Expected future compensation expense, restricted shares remaining vesting period	2 years 11 months 1 day
Restricted Shares Awarded on March 20, 2017 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	1,559
Date of Award	Apr. 10, 2018
Expected future remaining compensation expense \| $	$ 23
Expected future compensation expense, restricted shares remaining vesting period	9 months
Restricted Shares Awarded on April 10, 2018 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	4,373
Date of Award	Mar. 14, 2019
Expected future remaining compensation expense \| $	$ 69
Expected future compensation expense, restricted shares remaining vesting period	1 year 9 months
Restricted Shares Awarded on March 14, 2019 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	4,304
Date of Award	Mar. 14, 2020
Expected future remaining compensation expense \| $	$ 64
Expected future compensation expense, restricted shares remaining vesting period	9 months
Restricted Shares Awarded on March 14, 2019 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	7,798
Date of Award	Mar. 14, 2020
Expected future remaining compensation expense \| $	$ 135
Expected future compensation expense, restricted shares remaining vesting period	2 years 9 months
Restricted Shares Awarded on March 14, 2020 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	13,030
Date of Award	Mar. 03, 2021
Expected future remaining compensation expense \| $	$ 212
Expected future compensation expense, restricted shares remaining vesting period	3 years 9 months
Restricted Shares Awarded on March 14, 2019 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	13,692
Date of Award	Mar. 03, 2021
Expected future remaining compensation expense \| $	$ 230
Expected future compensation expense, restricted shares remaining vesting period	1 year 9 months
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	14,750
Date of Award	Mar. 03, 2022
Expected future remaining compensation expense \| $	$ 325
Expected future compensation expense, restricted shares remaining vesting period	4 years 9 months
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	17,024
Date of Award	Mar. 03, 2022
Expected future remaining compensation expense \| $	$ 374
Expected future compensation expense, restricted shares remaining vesting period	2 years 9 months
Restricted Stock [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Nonvested at beginning of period	69,840
Number of Restricted Shares, Granted	31,774
Number of Restricted Shares, Vested	(25,084)
Number of Restricted Shares, Forfeited	0
Number of Restricted Shares, Nonvested at end of period	76,530
Weighted Average Grant Date Fair Value, Nonvested at beginning of period \| $ / shares	$ 20.14
Weighted Average Grant Date Fair Value, Granted \| $ / shares	24.51
Weighted Average Grant Date Fair Value, Vested \| $ / shares	24.62
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	0
Weighted Average Grant Date Fair Value, Nonvested at end of period \| $ / shares	$ 21.87

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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 number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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