Goodwill And Intangible Assets (Schedule Of Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended	12 Months Ended
	Sep. 30, 2012	Dec. 31, 2011
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 12,632	$ 12,309
Accumulated Amortization	(5,723)	(4,421)
Net Carrying Value	6,909	7,888
Weighted Average Useful Life (in Years)	4 years 3 months 18 days	4 years 10 months 24 days
Developed Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	7,512	7,352
Accumulated Amortization	(3,264)	(2,570)
Net Carrying Value	4,248	4,782
Weighted Average Useful Life (in Years)	4 years 9 months 18 days	5 years 6 months
Trade Names [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,279	3,188
Accumulated Amortization	(1,748)	(1,356)
Net Carrying Value	1,531	1,832
Weighted Average Useful Life (in Years)	3 years 4 months 24 days	3 years 8 months 12 days
Other Intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,841	1,769
Accumulated Amortization	(711)	(495)
Net Carrying Value	$ 1,130	$ 1,274
Weighted Average Useful Life (in Years)	4 years 4 months 24 days	4 years 10 months 24 days