Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Rent expense	$ 11,500	$ 9,800	$ 8,600
Percentage of weighted average cost of capital	13.70%	13.90%
Severance	$ 0	$ 3,716	$ 0