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Cash and Due from Banks (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Other disclosures |  |
Balances | $ 11.0 | $ 11.8
Federal Reserve Bank average regulatory reserve |  |
Other disclosures |  |
Balances | $ 10.6 | $ 10.5

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- Definition The amount of average compensating balance arrangement that is maintained with the Reserve Bank, under an agreement for a bank loan or future credit availability. + References No definition available. + Details
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Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition The amount of a specific compensating balance arrangement that is maintained under an agreement for a bank loan or future credit availability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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Balance Type: | debit
Period Type: | instant

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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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Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |