Equity Incentive Plan - Summary of Company's Outstanding Restricted Stock (Detail) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) $ / shares shares	Sep. 30, 2022 USD ($) $ / shares shares
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		71,748
Expected future remaining compensation expense \| $	$ 1,078	$ 1,078
Expected future compensation expense, restricted shares remaining vesting period		2 years 4 months 9 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 remaining compensation expense \| $	8	$ 8
Expected future compensation expense, restricted shares remaining vesting period		3 months
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 \| $	49	$ 49
Expected future compensation expense, restricted shares remaining vesting period		1 year 3 months
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 remaining compensation expense \| $	21	$ 21
Expected future compensation expense, restricted shares remaining vesting period		3 months
Restricted Shares Awarded on March 14, 2020 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		6,951
Date of Award		Mar. 14, 2020
Expected future remaining compensation expense \| $	106	$ 106
Expected future compensation expense, restricted shares remaining vesting period		2 years 3 months
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		11,359
Date of Award		Mar. 03, 2021
Expected future remaining compensation expense \| $	170	$ 170
Expected future compensation expense, restricted shares remaining vesting period		3 years 3 months
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 \| $	164	$ 164
Expected future compensation expense, restricted shares remaining vesting period		1 year 3 months
Restricted Shares Awarded on March 3, 2022 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		12,914
Date of Award		Mar. 03, 2022
Expected future remaining compensation expense \| $	264	$ 264
Expected future compensation expense, restricted shares remaining vesting period		4 years 3 months
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 \| $	$ 296	$ 296
Expected future compensation expense, restricted shares remaining vesting period		2 years 3 months
Restricted Stock [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Nonvested at beginning of period	71,748	69,840
Number of Restricted Shares, Granted	0	31,774
Number of Restricted Shares, Vested	0	(27,728)
Number of Restricted Shares, Forfeited	0	(2,138)
Number of Restricted Shares, Nonvested at end of period	71,748	71,748
Weighted Average Grant Date Fair Value, Nonvested at beginning of period \| $ / shares	$ 21.88	$ 20.14
Weighted Average Grant Date Fair Value, Granted \| $ / shares	0	24.51
Weighted Average Grant Date Fair Value, Vested \| $ / shares	0	24.28
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	0	21.99
Weighted Average Grant Date Fair Value, Nonvested at end of period \| $ / shares	$ 21.88	$ 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
-Publisher FASB
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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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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