Goodwil And Intangible Assets, Net (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill and Intangible Assets, Net [Abstract]
Goodwill, Impairment Loss	$ 0	$ 0	$ 0
Intangible assets impairments	0	2,200,000
Aggregate amortization expense	$ 9,000,000	$ 9,500,000	$ 10,400,000