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Short-term Borrowings - Interest Expense on Short-Term Borrowings (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Interest On Short Term Borrowings [Line Items] |  |  |
Total interest on short-term borrowings | $ 704 | $ 8,298 | $ 10,741
Federal funds purchased |  |  |
Interest On Short Term Borrowings [Line Items] |  |  |
Total interest on short-term borrowings | 44 | 204 | 180
Borrowings from FHLB |  |  |
Interest On Short Term Borrowings [Line Items] |  |  |
Total interest on short-term borrowings | 434 | 7,313 | 9,929
Securities sold under agreements to repurchase |  |  |
Interest On Short Term Borrowings [Line Items] |  |  |
Total interest on short-term borrowings | $ 226 | $ 781 | $ 632

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- Definition The aggregate interest expense incurred on short-term borrowings including commercial paper and Federal funds purchased and securities sold under agreements to repurchase. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.7) -URI http://asc.fasb.org/extlink&oid=116637391&loc=SL114874048-224260 + Details
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