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Loans - Recorded Investment in Nonaccrual Loans by Portfolio Class of Loans (Detail) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015 | Mar. 31, 2015
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Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | $ 2,003 | $ 2,041 | $ 2,424
Agricultural Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | 162 | 162 |
Consumer Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | 1,196 | 1,155 |
Commercial Real Estate [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | 422 | 484 |
Consumer [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | 23 | 38 |
Commercial and Industrial [Member] |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Investment in nonaccrual loans | $ 200 | $ 202 |

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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5111-111524 + Details
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