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Fair Value - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Provision expense for (recoveries from) credit losses | $ (17,356) | $ 16,950 |  |
Net carrying amount other real estate owned and other repossessed property | 15 |  |  |
Other real estate owned property write-downs | 23 | 11 |  |
Valuation allowance for loan servicing rights with impairments | 146 | 1,443 | $ 1,407 | $ 31
Valuation allowance for loan servicing rights with impairments, impairments (recoveries) during period | $ (1,261) | 1,412 |  |
Past due period of mortgage loans held for sale, days | 90 days |  |  |
Interest income for residential loans held for sale | $ 400 | 400 |  |
Impaired Commercial and Commercial Real Estate Loans |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |  |
Principal amount of impaired commercial and commercial real estate loans | 35,900 |  | 57,200 |
Valuation allowance | 4,500 |  | $ 5,800 |
Provision expense for (recoveries from) credit losses | $ (200) | $ 6,800 |  |

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- Definition Net carrying amount of foreclosed assets measured on a non-recurring basis, including other real estate owned and other repossessed property. + References No definition available. + Details
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- Definition Amount of write downs on foreclosed assets measured on a non-recurring basis during the period, including other real estate owned and other repossessed property. + References No definition available. + Details
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- Definition Number of days past due in relation to loans held for sale. + References No definition available. + Details
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- Definition Principal amount of impaired commercial and commercial real estate loans. + References No definition available. + Details
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- Definition The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121581245&loc=d3e21338-158488 + Details
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- Definition 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. + References No definition available. + Details
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- Definition Interest and fee income from commercial and residential real estate loans. + 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 210.9-04.1) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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- Definition Amount of credit loss expense (reversal of expense) for financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04(11)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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- Definition Reflects the estimated amount of impairment as of the balance sheet date of recognized servicing assets that are being amortized in proportion to and over the period of estimated net servicing income or loss. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746 + Details
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- Definition Amount of increase (decrease) in the valuation allowance for impairment of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer from expenses (recoveries) recognized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (e)(2) -URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746 + Details
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