Equity Incentive Plan - Summary of Company's Restricted Stock (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) $ / shares shares
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	70,475
Expected future remaining compensation expense \| $	$ 905
Expected future compensation expense, restricted shares remaining vesting period	2 years 1 month 2 days
Restricted Shares Awarded on April 10, 2018 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	1,470
Date of Award	Apr. 10, 2018
Expected future compensation expense, restricted shares remaining vesting period	0 years
Restricted Shares Awarded on March 14, 2019 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	4,034
Date of Award	Mar. 14, 2019
Expected future remaining compensation expense \| $	$ 40
Expected future compensation expense, restricted shares remaining vesting period	1 year
Restricted Shares Awarded on March 14, 2020 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	4,304
Date of Award	Mar. 14, 2020
Expected future compensation expense, restricted shares remaining vesting period	0 years
Restricted Shares Awarded on March 14, 2020 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	6,669
Date of Award	Mar. 14, 2020
Expected future remaining compensation expense \| $	$ 90
Expected future compensation expense, restricted shares remaining vesting period	2 years
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	10,858
Date of Award	Mar. 03, 2021
Expected future remaining compensation expense \| $	$ 150
Expected future compensation expense, restricted shares remaining vesting period	3 years
Restricted Shares Awarded on March 3, 2021 [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 \| $	$ 131
Expected future compensation expense, restricted shares remaining vesting period	1 year
Restricted Shares Awarded on March 3, 2022 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted	12,424
Date of Award	Mar. 03, 2022
Expected future remaining compensation expense \| $	$ 236
Expected future compensation expense, restricted shares remaining vesting period	4 years
Restricted Shares Awarded on March 3, 2022 [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 \| $	$ 258
Expected future compensation expense, restricted shares remaining vesting period	2 years
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	(27,728)
Number of Restricted Shares, Forfeited	(3,411)
Number of Restricted Shares, Nonvested at end of period	70,475
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	24.28
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	21.88
Weighted Average Grant Date Fair Value, Nonvested at end of period \| $ / shares	$ 21.88

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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