Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Tax (expense) benefit on net unrealized gains arising during the period	$ (631)	$ (1,976)	$ (792)	$ (7,487)
Tax (expense) benefit of amortization of net unrealized holding gains to income	$ 217	$ 304	$ 435	$ 623