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Federal Funds Purchased and Securities Sold Under Agreement to Repurchase - Daily Securities Sold under Agreement to Repurchase (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amount Outstanding at End of Period	$ 27,200
Securities Sold under Agreements to Repurchase [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amount Outstanding at End of Period	$ 27,218	$ 28,218
Weighted Average Rate End of Period	0.99%	0.98%
Maximum Amount Borrowings Outstanding Month End	$ 27,218	$ 28,968
Approximate Average Outstanding in Period	$ 27,574	$ 28,918
Approximate Weighted Average Interest Rate For the Period	4.00%	3.97%
Daily Securities Sold Under Agreement to Repurchase [Member]
Schedule of Trading Securities and Other Trading Assets [Line Items]
Weighted Average Rate End of Period	0.00%	0.00%
Maximum Amount Borrowings Outstanding Month End	$ 523	$ 1,694
Approximate Average Outstanding in Period	$ 79	$ 1,176
Approximate Weighted Average Interest Rate For the Period	3.77%	1.19%

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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