Segment Information (Schedule of Additional Business Segment Information) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Assets	$ 1,212,840	$ 1,162,460
Specialty Commercial Segment [Member]
Segment Reporting Information [Line Items]
Assets	782,301	734,763
Standard Commercial Segment [Member]
Segment Reporting Information [Line Items]
Assets	164,915	164,295
Personal Segment [Member]
Segment Reporting Information [Line Items]
Assets	239,882	241,686
Corporate [Member]
Segment Reporting Information [Line Items]
Assets	$ 25,742	$ 21,716