Equity Incentive Plan - Summary of Company's Outstanding Restricted Stock (Detail) $ / shares in Units, $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) $ / shares shares	Jun. 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 \| $	$ 1,231	$ 1,231
Expected future compensation expense, restricted shares remaining vesting period		2 years 7 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 \| $	15	$ 15
Expected future compensation expense, restricted shares remaining vesting period		6 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 \| $	59	$ 59
Expected future compensation expense, restricted shares remaining vesting period		1 year 6 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 \| $	42	$ 42
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		6,951
Date of Award		Mar. 14, 2020
Expected future remaining compensation expense \| $	118	$ 118
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		11,359
Date of Award		Mar. 03, 2021
Expected future remaining compensation expense \| $	183	$ 183
Expected future compensation expense, restricted shares remaining vesting period		3 years 6 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 \| $	197	$ 197
Expected future compensation expense, restricted shares remaining vesting period		1 year 6 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 \| $	282	$ 282
Expected future compensation expense, restricted shares remaining vesting period		4 years 6 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 \| $	$ 335	$ 335
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	76,530	69,840
Number of Restricted Shares, Granted	0	31,774
Number of Restricted Shares, Vested	(2,644)	(27,728)
Number of Restricted Shares, Forfeited	(2,138)	(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	$ 21.87	$ 20.14
Weighted Average Grant Date Fair Value, Granted \| $ / shares	0	24.51
Weighted Average Grant Date Fair Value, Vested \| $ / shares	21.57	24.28
Weighted Average Grant Date Fair Value, Forfeited \| $ / shares	21.99	21.99
Weighted Average Grant Date Fair Value, Nonvested at end of period \| $ / shares	$ 21.88	$ 21.88

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Share based compensation arrangement by share based payment award date.

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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
-Name Accounting Standards Codification
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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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