Income Tax Expense Benefit Continuing Operations Increase Decrease By Items Reconciliation [Abstract]

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operations attributable to deduction. Includes, but is not limited to, dividend deduction, deduction for dividend paid to employee stock ownership plan (ESOP), Medicare prescription drug benefit subsidy deduction, and other deductions.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority noncontrolling interest income (loss), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, increase (decrease) in enacted tax rate, prior year income taxes, increase (decrease) in deferred tax asset valuation allowance, and other adjustments.

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Income Taxes - Reconciliation of the Statutory Federal Income Tax Rate to the Effective Tax Rate (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]
Federal income tax at statutory rates									$ 5,954	$ 8,489	$ 6,194
(Decrease) increase resulting from:
State income tax, net of federal benefit									264	239	167
Tax exempt interest									(129)	(133)	(116)
Section 831 deduction									(187)	(270)	(294)
Other									(335)	(365)	51
Total Income Tax	$ 1,332	$ 1,121	$ 1,531	$ 1,583	$ 1,706	$ 2,253	$ 2,050	$ 1,951	$ 5,567	$ 7,960	$ 6,002