Goodwill and Other Intangible Assets (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Finite-Lived Intangible Assets [Line Items]
Intangible amortization	$ 6,530	$ 6,747	$ 6,069
Core deposit intangible
Finite-Lived Intangible Assets [Line Items]
Intangible amortization	6,399	6,616	5,938
Customer relationship intangible
Finite-Lived Intangible Assets [Line Items]
Intangible amortization	$ 131	$ 131	$ 131