Segment Information (Summary Of Financial Information By Segment) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Hosted services – Business	$ 150,004	$ 132,310	$ 111,934
Hosted services – Consumer	15,091	15,111	14,522
Professional services	12,710	9,988	6,633
Total revenue	177,805	157,409	133,089
Cost of revenue	42,555	35,579	33,195
Sales and marketing	62,488	49,614	38,884
Amortization of purchased intangibles	871	218	109
Unallocated corporate expenses	76,365	61,657	41,266
(Loss) income from operations	(4,474)	10,341	19,635
Corporate [Member]
Segment Reporting Information [Line Items]
Unallocated corporate expenses	76,365	61,657	41,266
(Loss) income from operations	(76,365)	(61,657)	(41,266)
Business [Member]
Segment Reporting Information [Line Items]
Hosted services – Business	150,004	132,310	111,934
Professional services	12,710	9,988	6,633
Total revenue	162,714	142,298	118,567
Cost of revenue	40,132	33,450	29,793
Sales and marketing	57,011	44,087	32,690
Amortization of purchased intangibles	871	218	109
(Loss) income from operations	64,700	64,543	55,975
Consumer [Member]
Segment Reporting Information [Line Items]
Hosted services – Consumer	15,091	15,111	14,522
Total revenue	15,091	15,111	14,522
Cost of revenue	2,423	2,129	3,402
Sales and marketing	5,477	5,527	6,194
(Loss) income from operations	$ 7,191	$ 7,455	$ 4,926