Fair Value Disclosures - Fair Value Information for Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	$ 200,148	$ 191,513
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	200,148	191,513
Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	4,133	4,183
Fair Value on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	202,148	194,938
Total liabilities at fair value on a recurring basis	78	388
Fair Value on a Recurring Basis [Member] | U.S. Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	41,698	37,389
Fair Value on a Recurring Basis [Member] | GSE - Mortgage-backed Securities and CMO's [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	50,463	41,496
Fair Value on a Recurring Basis [Member] | Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	38,344	39,281
Fair Value on a Recurring Basis [Member] | State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	65,510	69,164
Fair Value on a Recurring Basis [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	411	1,352
Fair Value on a Recurring Basis [Member] | Mortgage Banking Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	1,589	2,073
Total liabilities at fair value on a recurring basis	78	388
Fair Value on a Recurring Basis [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	411	1,352
Fair Value on a Recurring Basis [Member] | Level 1 [Member] | Equity Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	411	1,352
Fair Value on a Recurring Basis [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	200,262	191,513
Total liabilities at fair value on a recurring basis	78	388
Fair Value on a Recurring Basis [Member] | Level 2 [Member] | U.S. Government Agencies [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	41,698	37,389
Fair Value on a Recurring Basis [Member] | Level 2 [Member] | GSE - Mortgage-backed Securities and CMO's [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	50,463	41,496
Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Asset-backed Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	38,344	39,281
Fair Value on a Recurring Basis [Member] | Level 2 [Member] | State and Political Subdivisions [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	65,510	69,164
Fair Value on a Recurring Basis [Member] | Level 2 [Member] | Mortgage Banking Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	114
Total liabilities at fair value on a recurring basis	78	388
Fair Value on a Recurring Basis [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	1,475	2,073
Fair Value on a Recurring Basis [Member] | Level 3 [Member] | Mortgage Banking Derivatives [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	1,475	2,073
Fair Value on a Recurring Basis [Member] | Corporate Bonds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	4,133	4,183
Fair Value on a Recurring Basis [Member] | Corporate Bonds [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value on a recurring basis	$ 4,133	$ 4,183