Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Revenue:
Subscription revenue	$ 9,222	$ 8,332
Other revenue	831	984
Total revenue	10,053	9,316
Operating expenses:
Cost of subscription revenue	2,480	1,868
Cost of other revenue	766	707
Total cost of revenue, exclusive of depreciation and amortization shown below:	3,246	2,575
Research and development	3,250	3,408
Sales and marketing	4,630	3,156
General and administrative	3,167	2,882
Depreciation and amortization	1,400	995
Total operating expenses	15,693	13,016
Operating loss	(5,640)	(3,700)
Interest and other expense, net	(171)	(114)
Change in fair value of warrant liability		5
Loss before income taxes	(5,811)	(3,809)
Income tax provision	(10)	(8)
Net loss	(5,821)	(3,817)
Dividends related to Series B convertible preferred stock	(143)	(147)
Net loss available to common stockholders	$ (5,964)	$ (3,964)
Per share of common stock:
Basic net loss available to common stockholders	$ (0.24)	$ (0.18)
Diluted net loss available to common stockholders	$ (0.24)	$ (0.18)
Shares used to calculate basic net loss per share	25,064	21,877
Shares used to calculate diluted net loss per share	25,064	21,877
Stock-based compensation is included in individual line items above:
Stock-based compensation	$ 1,600	$ 1,400
Total Cost of Revenue [Member]
Stock-based compensation is included in individual line items above:
Stock-based compensation	74	59
Research and Development [Member]
Stock-based compensation is included in individual line items above:
Stock-based compensation	329	266
Sales and Marketing [Member]
Stock-based compensation is included in individual line items above:
Stock-based compensation	479	366
General and Administrative [Member]
Stock-based compensation is included in individual line items above:
Stock-based compensation	$ 743	$ 674