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Funds Restrictions and Reserve Balance - Additional Information (Detail) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Aggregate amount of unrestricted funds | $ 4.5 |
First Bank |  |
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items] |  |
Aggregate amounts of daily average required balances of reserve against its deposits | $ 7.4 | $ 6.0

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- Definition Aggregate amount of daily average deposit. + References No definition available. + Details
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Balance Type: | debit
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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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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |