Premises and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 69,798	$ 65,669
Less accumulated depreciation	40,205	38,174
Total premises and equipment, net	29,593	27,495
Depreciation expense	3,400	3,100	$ 3,300
Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	6,020	6,020
Premises and Improvements [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	36,358	34,608
Furniture, Fixtures and Equipment [Member]
Property, Plant and Equipment [Line Items]
Premises and equipment, gross	$ 27,420	$ 25,041