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Commitments and Contingent Liabilities (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Commitments and Contingent Liabilities (Additional Textual) [Abstract]
Maximum commitment period to make loans	30 days
Standby letters of credit contractual value	$ 4,900,000	$ 4,300,000
Maximum subscription amount committed in SBIC investment funds	8,000,000
Investment in SBIC funds	$ 5,000,000
Fixed Rate
Commitments and Contingent Liabilities (Textual) [Abstract]
Fixed rate loan commitments maturity range		15 years
Commitments and Unused Lines of Credit | Minimum
Commitments and Contingent Liabilities (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	2.99%	0.10%
Commitments and Unused Lines of Credit | Maximum
Commitments and Contingent Liabilities (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage	16.00%	18.00%
Commitments to make loans | Minimum
Commitments and Contingent Liabilities (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage		4.25%
Debt Instrument, Variable Interest Rate Percentage		4.69%
Commitments to make loans | Maximum
Commitments and Contingent Liabilities (Textual) [Abstract]
Debt Instrument, Interest Rate, Stated Percentage		5.25%
Debt Instrument, Variable Interest Rate Percentage		5.75%

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Commitments and Contingent Liabilities (Additional Textual) [Abstract]

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Commitments and Contingent Liabilities (Textual) [Abstract]

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Debt instrument variable interest rate.

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Maximum commitment period to make loans.

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Maximum subscription amount committed in SBIC investment funds.

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Standby letters of credit contractual amount.

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Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3213-108585

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