Income Taxes (Provision for Income Taxes) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Current expense:
Federal	$ 12,329	$ 43,850	$ 5,465
State	6,763	13,039	(362)
Foreign	3,435	6,573	1,126
Total current	22,527	63,462	6,229
Deferred (benefit) expense:
Federal	(30,021)	(3,054)	19,583
State	5,560	(5,302)	2,735
Foreign	1,365	(1,813)
Total deferred	(23,096)	(10,169)	22,318
Total provision	$ (569)	$ 53,293	$ 28,547