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Securities (Details Textual)	3 Months Ended		9 Months Ended
	Sep. 30, 2017 USD ($) Securities	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) Securities	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Proceeds from sales of securities available for sale	$ 0	$ 2,300,000	$ 54,493,000	$ 11,480,000
Gross gains realized	0	31,000	730,000	224,000
Gross Losses realized	0	$ 0	731,000	$ 152,000
Unrealized losses	$ 1,696,000		$ 1,696,000		$ 1,666,000
Number of securities | Securities	541		541
Number of securities on unrealized loss position | Securities	137		137
U.S. Treasury and U.S. government sponsored entities
Schedule Of Available For Sale Securities [Line Items]
Unrealized losses	$ 13,000		$ 13,000		$ 0
U.S. Treasury and U.S. government sponsored entities | Maximum
Schedule Of Available For Sale Securities [Line Items]
Unrealized losses	$ 1,000		$ 1,000

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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-Publisher FASB
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The cash inflow associated with the sale of debt and equity securities classified as available-for-sale securities.

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