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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
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Dec. 31, 2023 | Dec. 31, 2022
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period | $ 28,200 |
Daily Securities Sold Under Agreement to Repurchase [Member] |  |
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period |  | $ 1,115
Weighted Average Rate End of Period | 0.00% | 0.95%
Maximum Amount Borrowings Outstanding Month End | $ 1,694 | $ 1,450
Approximate Average Outstanding in Period | $ 1,176 | $ 1,169
Approximate Weighted Average Interest Rate For the Period | 1.19% | 0.43%
Term CDs Sold Under Agreement to Repurchase [Member] |  |
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period | $ 28,218 | $ 30,518
Weighted Average Rate End of Period | 0.98% | 0.97%
Maximum Amount Borrowings Outstanding Month End | $ 28,968 | $ 34,504
Approximate Average Outstanding in Period | $ 28,918 | $ 31,573
Approximate Weighted Average Interest Rate For the Period | 3.97% | 2.54%

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.12-12A(Column A)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.12-12(Column A)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 6 -Subparagraph (SX 210.12-14(Column A)(Footnote 2)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-6 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 946 -SubTopic 320 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-12B(Column A)(Footnote 4)(b)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480032/946-320-S99-3 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483466/210-20-50-3 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(i)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org//1943274/2147483444/210-20-55-10 Reference 9: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 + Details
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