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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, 2021 | Dec. 31, 2020
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period | $ 29,300 |
Daily Securities Sold Under Agreement to Repurchase [Member] |  |
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period | $ 1,062 | $ 1,899
Weighted Average Rate End of Period | 0.70% | 1.08%
Maximum Amount Borrowings Outstanding Month End | $ 1,991 | $ 2,568
Approximate Average Outstanding in Period | $ 1,514 | $ 1,765
Approximate Weighted Average Interest Rate For the Period | 0.43% | 1.00%
Term CDs Sold Under Agreement to Repurchase [Member] |  |
Schedule of Trading Securities and Other Trading Assets [Line Items] |  |
Amount Outstanding at End of Period | $ 28,206 | $ 28,340
Weighted Average Rate End of Period | 1.00% | 1.00%
Maximum Amount Borrowings Outstanding Month End | $ 28,362 | $ 29,261
Approximate Average Outstanding in Period | $ 28,315 | $ 28,379
Approximate Weighted Average Interest Rate For the Period | 2.56% | 2.52%

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(i)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(1)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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