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Securities - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Schedule of Available-for-sale Securities [Line Items]
Investments pledged, carrying value	$ 238,100,000		$ 238,100,000		$ 221,900,000
Other securities	11,509,000		11,509,000		14,400,000
Proceeds from sales of securities			1,374,000	$ 0
Gross realized gain (losses)	0	$ 0	0	$ 0
Federal Home Loan Bank of Cincinnati and Indianapolis Stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Other securities	11,500,000		11,500,000		14,400,000
Federal Reserve's Bank Term Funding Program [Member]
Schedule of Available-for-sale Securities [Line Items]
Investments pledged, carrying value	$ 29,000,000		$ 29,000,000		$ 29,900,000

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Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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