Transactions with Executive Officers, Directors, and Principal Shareholders - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Related Party Transaction [Line Items]
Percentage of gross revenue	5.00%
Percentage of aggregate amount of consolidated assets	5.00%
Director
Related Party Transaction [Line Items]
Related party deposits	$ 10,600,000	$ 6,400,000
Minimum
Related Party Transaction [Line Items]
Percentage of participation in equity	10.00%
Line of Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Available credit line	$ 1,800,000	1,800,000.0
Letter of Credit \| Affiliated Entity
Related Party Transaction [Line Items]
Outstanding commitment	500,000
Unfunded Loan Commitment \| Affiliated Entity
Related Party Transaction [Line Items]
Commitment to provide short-term commercial real estate financing	$ 8,000,000	$ 8,000,000

Benchmark percentage of aggregate assets for related party transactions

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- Definition

Benchmark percentage of gross revenues for related party transactions.

+ References

No definition available.

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- Definition

Percentage of participation in equity.

+ References

No definition available.

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- Definition

Amount of payable due to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount of deposits held by the entity for a related party (entity, shareholder, employee).

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-Name Accounting Standards Codification
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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.

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