Summary of Significant Accounting Policies (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Accounting Policies [Line Items]
Federal Reserve Bank, reserve requirement	$ 16,546,000	$ 15,208,000
Foreclosed assets	3,254,392	2,386,239
Amortization of intangible assets	346,435	305,452
Impairment of intangible assets	0
Advertising Expense	637,600	615,751
Residential Real Estate [Member]
Accounting Policies [Line Items]
Foreclosed assets	545,750	1,500
Mortgage loans in process of foreclosure	$ 0	$ 0
Minimum [Member] \| Building and Leasehold Improvements [Member]
Accounting Policies [Line Items]
Useful life	15 years
Minimum [Member] \| Furniture and Equipment [Member]
Accounting Policies [Line Items]
Useful life	3 years
Maximum [Member] \| Building and Leasehold Improvements [Member]
Accounting Policies [Line Items]
Useful life	40 years
Maximum [Member] \| Furniture and Equipment [Member]
Accounting Policies [Line Items]
Useful life	7 years

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Amount of cash or deposit reserve required to be maintained with federal reserve bank.

+ References

No definition available.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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-Publisher FASB
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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

+ References

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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-Name Accounting Standards Codification
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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