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Investment Securities (Details Textual)	6 Months Ended
	Jun. 30, 2018 USD ($) Investments	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) Investments
Investment Securities (Textual)
Sale of investment securities	$ 5,800,000	$ 415,000
Loss on sale of investments securities	$ 1,000
Gain on sale of investment securities		$ 2,000
Fair market value, less than 12 months, number of investments | Investments	33		25
Fair market value, less than 12 months	$ 36,400,000
Fair market value, 12 months or longer, number of investments | Investments	31		28
Fair market value, 12 months or longer	$ 28,300,000
Securities pledged as collateral for repurchase agreements from brokers	$ 4,200,000		$ 7,700,000

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Investment securities.

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Investments with fair market value in continuous unrealized loss position for less than twelve months.

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Investments with fair market value In continuous unrealized loss position twelve months or longer.

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Number of investments in continuous unrealized loss position, less than twelve months.

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Number of investments in continuous unrealized loss position twelve months or longer.

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Amount of restricted investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(i)
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The difference between the carrying value and the sale price of an investment. A gain would be recognized when the sale price of the investment is greater than the carrying value of the investment. This element refers to the Gain included in earnings and not to the cash proceeds of the sale.

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