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Loan and Lease Receivables - Summary of Outstanding Balance and Carrying Amount of All Acquired Impaired Loans (Details) - Acquired Impaired Loans - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | $ 476,980 | $ 555,709
Carrying Value | 327,690 | 404,037
Commercial Real Estate |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | 235,898 | 278,893
Carrying Value | 166,712 | 207,303
Residential Real Estate |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | 207,660 | 236,384
Carrying Value | 144,562 | 175,717
Construction, Land Development, and Other Land |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | 13,270 | 15,292
Carrying Value | 5,946 | 6,979
Commercial and Industrial |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | 18,333 | 23,164
Carrying Value | 10,008 | 13,464
Installment and Other |  |
Accounts Notes And Loans Receivable [Line Items] |  |
Outstanding Balance | 1,819 | 1,976
Carrying Value | $ 462 | $ 574

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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 The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 + Details
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- Definition The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=82894507&loc=d3e13503-111538 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=82894903&loc=d3e15032-111544 + Details
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