Stock Options And Employee Stock Purchase Plan (Assumptions To Estimate Fair Value Of Stock Options) (Details)	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Estimated forfeiture rate	12.47%	11.07%

Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Estimated Forfeiture Rate

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