Fair Value Measurements and Disclosure - Summary of Carrying Amounts and Estimated Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financial Assets: (Carrying Amount)
Cash and cash equivalents	$ 172,067	$ 150,557
Securities available-for-sale at fair value	118,098	91,352
Securities held-to-maturity	167	193
Loans receivable, net	1,552,613	1,529,843
Restricted bank stock	1,398	1,410
Accrued interest receivable	6,405	6,089
Equity method investments	9,051	8,296
Mortgage servicing rights	1,383
Financial Liabilities (Carrying Amount)
Deposits	1,705,620	1,635,741
Accrued interest payable	11,831	9,162
Financial Assets: (Fair Value)
Securities available-for-sale at fair value	118,098	91,352
Securities held-to-maturity	199	200
Fair Value, Inputs, Level 1, Level 2, and Level 3 [Member]
Financial Assets: (Fair Value)
Cash and cash equivalents	172,067	150,557
Securities available-for-sale at fair value	118,098	91,352
Securities held-to-maturity	167	192
Loans receivable, net	1,495,787	1,425,814
Restricted bank stock	1,398	1,410
Accrued interest receivable	6,405	6,089
Equity method investments	9,051	8,296
Mortgage servicing rights	1,383
Financial Liabilities (Fair Value)
Deposits	1,705,620	1,581,762
Accrued interest payable	11,831	9,162
Fair Value, Inputs, Level 1 [Member]
Financial Assets: (Fair Value)
Cash and cash equivalents	172,067	150,557
Fair Value, Inputs, Level 2 [Member]
Financial Assets: (Fair Value)
Securities available-for-sale at fair value	118,098	91,352
Securities held-to-maturity	167	192
Restricted bank stock	1,398	1,410
Accrued interest receivable	6,405	6,089
Equity method investments	5,900	5,900
Mortgage servicing rights	1,383
Financial Liabilities (Fair Value)
Deposits	1,705,620	1,581,762
Accrued interest payable	11,831	9,162
Fair Value, Inputs, Level 3 [Member]
Financial Assets: (Fair Value)
Loans receivable, net	1,495,787	1,425,814
Equity method investments	$ 3,151	$ 2,396