Equity Incentive Plan - Summary of Company's Outstanding Restricted Stock (Detail) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023 USD ($) $ / shares shares	Jun. 30, 2023 USD ($) $ / shares shares
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		88,422
Expected future remaining compensation expense \| $	$ 1,485	$ 1,485
Expected future compensation expense, restricted shares remaining vesting period		2 years 10 months 13 days
Restricted Shares Awarded on March 14, 2019 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		1,924
Date of Award		Mar. 14, 2019
Expected future remaining compensation expense \| $	19	$ 19
Expected future compensation expense, restricted shares remaining vesting period		6 months
Restricted Shares Awarded on March 14, 2020 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		4,265
Date of Award		Mar. 14, 2020
Expected future remaining compensation expense \| $	62	$ 62
Expected future compensation expense, restricted shares remaining vesting period		1 year 6 months
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		7,776
Date of Award		Mar. 03, 2021
Expected future remaining compensation expense \| $	114	$ 114
Expected future compensation expense, restricted shares remaining vesting period		2 years 6 months
Restricted Shares Awarded on March 3, 2021 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		6,793
Date of Award		Mar. 03, 2021
Expected future remaining compensation expense \| $	65	$ 65
Expected future compensation expense, restricted shares remaining vesting period		6 months
Restricted Shares Awarded on March 3, 2022 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		9,554
Date of Award		Mar. 03, 2022
Expected future remaining compensation expense \| $	191	$ 191
Expected future compensation expense, restricted shares remaining vesting period		3 years 6 months
Restricted Shares Awarded on March 3, 2022 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		11,261
Date of Award		Mar. 03, 2022
Expected future remaining compensation expense \| $	191	$ 191
Expected future compensation expense, restricted shares remaining vesting period		1 year 6 months
Restricted Shares Awarded on March 14, 2023 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		17,103
Date of Award		Mar. 14, 2023
Expected future remaining compensation expense \| $	316	$ 316
Expected future compensation expense, restricted shares remaining vesting period		4 years 6 months
Restricted Shares Awarded on March 14, 2023 [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Granted		29,746
Date of Award		Mar. 14, 2023
Expected future remaining compensation expense \| $	$ 527	$ 527
Expected future compensation expense, restricted shares remaining vesting period		2 years 6 months
Restricted Stock [Member]
Schedule Of Nonvested Stock Option Activity [Line Items]
Number of Restricted Shares, Nonvested at beginning of period	88,422	70,096
Number of Restricted Shares, Granted	0	47,536
Number of Restricted Shares, Vested	0	(27,470)
Number of Restricted Shares, Forfeited		(1,740)
Number of Restricted Shares, Nonvested at end of period	88,422	88,422
Weighted Average Grant Date Fair Value, Nonvested at beginning of period \| $ / shares	$ 21.98	$ 21.88
Weighted Average Grant Date Fair Value, Granted \| $ / shares	0	21.85
Weighted Average Grant Date Fair Value, Vested \| $ / shares	0	21.52
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares		21.74
Weighted Average Grant Date Fair Value, Nonvested at end of period \| $ / shares	$ 21.98	$ 21.98

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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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
-Topic 718
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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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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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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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