Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) subsidiary	Dec. 31, 2016 USD ($)
Property, Plant and Equipment [Line Items]
Number of subsidiaries | subsidiary	3
Escrow deposits in conjunction with mortgage loans	$ 116	$ 196
Office Building [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, useful lives	39 years
Federal Funds Purchased Advances [Member]
Property, Plant and Equipment [Line Items]
Daily average required cash balances	$ 106,600	$ 43,600
Furniture and Fixtures [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, useful lives	15 years
Furniture and Fixtures [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, useful lives	3 years