Income Taxes (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
U.S. statutory rate	21.00%	35.00%
Effective tax rate	11.40%	(1.60%)
Unrecognized tax benefits	$ 2,500
Unrecognized tax benefits that would have a favorable impact on effective tax rate	2,200
Provision for income taxes	$ 28,643	$ 361