CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Income Statement [Abstract]
Revenue		$ 129,959,000	$ 131,218,000		$ 122,535,000
Cost of revenue	[1]	29,008,000	29,501,000		29,102,000
Gross profit		100,951,000	101,717,000		93,433,000
Operating expenses:
Sales and marketing		52,813,000	60,080,000	[1]	60,343,000	[1]
Research and development		19,200,000	22,359,000		21,868,000
General and administrative		25,136,000	26,784,000		27,800,000
Total operating expenses		97,149,000	109,223,000		110,011,000
Income (loss) from operations		3,802,000	(7,506,000)		(16,578,000)
Other income (expense):
Interest income (expense), net		754,000	510,000		222,000
Other (expense) income, net		(385,000)	9,000		83,000
Total other income (expense)		369,000	519,000		305,000
Income (loss) before income taxes		4,171,000	(6,987,000)		(16,273,000)
Income tax expense		689,000	614,000		284,000
Net income (loss)		$ 3,482,000	$ (7,601,000)		$ (16,557,000)
Net loss per share:
Basic (in dollars per share)		$ 0.12	$ (0.28)		$ (0.63)
Diluted (in dollars per share)		$ 0.12	$ (0.28)		$ (0.63)
Weighted average common shares outstanding:
Weighted Average Number of Shares Outstanding, Basic		27,886,278	27,138,274		26,366,748
Weighted Average Number of Shares Outstanding, Diluted		28,816,977	27,138,274		26,366,748

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