Noninterest Income - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
ASU 2014-09 [Member]
Disaggregation Of Revenue [Line Items]
Expense recognized on credit card rewards in other costs of operations	$ 24,000	$ 13,000	$ 38,000	$ 39,000

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.

No definition available.

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