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Commitments and Unfunded Credits - Financial Instruments Representing Credit Risk (Detail) - First Bank - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Stand-by letters of credit |  |
Other Commitments [Line Items] |  |
Contract amounts represent credit risk | $ 10,379 | $ 8,983
Commitments to extend credit and unfunded commitments under lines of credit |  |
Other Commitments [Line Items] |  |
Contract amounts represent credit risk | $ 77,992 | $ 71,421

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- Definition The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 + Details
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