Summary Of Significant Accounting Policies (Schedule Of Risk Concentration) (Details) (Customer Concentration Risk [Member])	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Concentration Risk [Line Items]
Revenue from channel partners	26.00%	26.00%	27.00%
Direct sale customers exceeding 5% of revenue	0	0	0
1st Largest Channel Partner [Member]
Concentration Risk [Line Items]
Revenue from channel partners	6.00%	4.00%	4.00%
2nd Largest Channel Partner [Member]
Concentration Risk [Line Items]
Revenue from channel partners	3.00%	3.00%	3.00%