Consolidated Statements of Income and Comprehensive Income - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenues		$ 34,796	$ 34,286	$ 66,212	$ 64,258
Cost of revenues	[1]	8,785	7,952	16,936	14,964
Gross profit		26,011	26,334	49,276	49,294
Operating expenses:
Selling and marketing	[1]	12,570	13,976	25,519	26,422
Product development	[1]	1,846	2,001	3,878	3,988
General and administrative	[1]	3,267	3,123	6,622	6,145
Depreciation and amortization, excluding depreciation of $221, $56, $392, and $69, respectively, included in cost of revenues		1,453	1,146	2,798	2,276
Total operating expenses		19,136	20,246	38,817	38,831
Operating income		6,875	6,088	10,459	10,463
Interest and other expense, net		(10)	(253)	(479)	(390)
Income before provision for income taxes		6,865	5,835	9,980	10,073
Provision for income taxes		2,092	1,684	3,000	2,632
Net income		4,773	4,151	6,980	7,441
Other comprehensive income (loss), net of tax:
Unrealized loss on investments (net of tax provision of $(24), $0, $13, and $0, respectively)		84		(48)
Foreign currency translation gain (loss)		21	(58)	(32)	(17)
Other comprehensive income (loss)		105	(58)	(80)	(17)
Comprehensive income		$ 4,878	$ 4,093	$ 6,900	$ 7,424
Net income per common share:
Basic		$ 0.17	$ 0.15	$ 0.25	$ 0.27
Diluted		$ 0.17	$ 0.15	$ 0.25	$ 0.26
Weighted average common shares outstanding:
Basic		27,533	27,640	27,768	27,723
Diluted		28,163	28,232	28,304	28,226

[1] Amounts include stock-based compensation expense as follows: