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Loans and Allowance for Credit Losses - Troubled Debt Restructured Loans and Commitments (Detail) - USD ($) $ in Thousands | Mar. 31, 2018 | Dec. 31, 2017
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Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Modifications, Recorded Investment | $ 28,940 | $ 22,785
Loans and Leases Receivable, Impaired, Commitment to Lend | 1,838 | 114
Letter of Credit [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Loans and Leases Receivable, Impaired, Commitment to Lend | 60 | 60
Unused lines of Credit [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Loans and Leases Receivable, Impaired, Commitment to Lend | 1,778 | 54
Accrual Loans [Member] [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Modifications, Recorded Investment | 18,707 | 11,563
Non Accrual Loans [Member] |  |
Financing Receivable, Troubled Debt Restructurings [Line Items] |  |
Financing Receivable, Modifications, Recorded Investment | $ 10,233 | $ 11,222

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- Definition Financing Receivable, Troubled Debt Restructurings [Line Items] [Line Items] + References No definition available. + Details
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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554 + Details
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- Definition Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554 + Details
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- Details
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