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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
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

X

- 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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X

- 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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- Details

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- Details

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- Details

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