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Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation Of Revenue [Line Items]
Revenue	$ 1,331	$ 1,186
Debit card income [Member]
Disaggregation Of Revenue [Line Items]
Revenue	588	530
Trust service fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue	502	411
Brokerage advisory fees [Member]
Disaggregation Of Revenue [Line Items]
Revenue	156	160
Service charges and fees related to deposit accounts [Member]
Disaggregation Of Revenue [Line Items]
Revenue	$ 85	$ 85

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- Definition

[Line Items] for Disaggregation Of Revenue [Table]

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- Definition

Revenue From Contract With Customer Excluding Assessed Tax

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