Income Taxes (Schedule of Income Tax Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Federal current	$ 7,428	$ 38,535	$ 237
State current	9,841	3,979	2,928
Foreign current	770	102	534
Current income tax expense (benefit), total	18,039	42,616	3,699
Federal deferred	37,284	(104,573)	42,895
State deferred	410	3,625	1,737
Deferred income tax expense (benefit), total	37,694	(100,948)	44,632
Total income tax expense (benefit)	$ 55,733	$ (58,332)	$ 48,331