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Fair Value of Financial Instruments - Impaired Loans (Detail) - Collateral Dependent Impaired Loans [Member] - USD ($) $ in Thousands | Mar. 31, 2021 | Dec. 31, 2020
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Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 4,130 | $ 7,703
Fair Value on Nonrecurring Basis [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | 4,130 | 7,703
Fair Value on Nonrecurring Basis [Member] | Level 3 [Member] |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |
Assets measured at fair value on a nonrecurring basis, Total | $ 4,130 | $ 7,703

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- Definition Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 45 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745 + Details
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