Investments (Schedule of Unrealized Appreciation) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016	Dec. 31, 2015
Investments [Abstract]
Net change in unrealized appreciation on available-for-sale securities before deferred tax	$ 1,754	$ (3,225)
Deferred income tax	(596)	1,097
Net change in unrealized appreciation on available-for-sale securities	$ 1,158	$ (2,128)