Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues:
Subscription	$ 55,279	$ 30,331	$ 141,640	$ 76,331
Professional services and other	9,066	3,866	26,910	12,563
Total revenues	64,345	34,197	168,550	88,894
Cost of revenues:
Subscription	17,931	6,323	43,182	15,538
Professional services and other	9,643	5,609	28,519	15,095
Total cost of revenues	27,574	11,932	71,701	30,633
Gross profit	36,771	22,265	96,849	58,261
Operating expenses(1):
Sales and marketing	28,140	13,980	74,356	34,375
Research and development	10,783	2,757	26,098	7,003
General and administrative	11,195	4,509	24,441	10,471
Total operating expenses	50,118	21,246	124,895	51,849
Income (loss) from operations	(13,347)	1,019	(28,046)	6,412
Interest and other income (expense), net	615	(729)	1,148	(412)
Income (loss) before provision for income taxes	(12,732)	290	(26,898)	6,000
Provision for income taxes	321	169	519	852
Net income (loss)	(13,053)	121	(27,417)	5,148
Net income (loss) per share attributable to common stockholders:
Basic	$ (0.11)		$ (0.49)	$ 0.05
Diluted	$ (0.11)		$ (0.49)	$ 0.04
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders:
Basic	117,698,005	20,693,359	57,089,411	19,695,440
Diluted	117,698,005	32,126,535	57,089,411	30,612,539
Other comprehensive income (loss) before tax:
Foreign currency translation and remeasurement adjustments	57	246	(479)	439
Unrealized loss on short-term investments	(17)		(34)
Provision for income taxes			60	48
Other comprehensive income (loss), net of tax	40	246	(573)	391
Comprehensive income (loss)	$ (13,013)	$ 367	$ (27,990)	$ 5,539