Unaudited Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues
Total revenues	$ 196,532	$ 175,006	$ 620,487	$ 544,262
Cost of revenues
Operating expenses	24,278	21,088	71,651	66,153
Depreciation and amortization	6,634	5,304	18,865	14,796
Total cost of revenues	30,912	26,392	90,516	80,949
Administrative expenses
Sales and marketing	62,146	47,060	173,228	128,280
Research and development	21,772	19,605	65,171	54,869
General and administrative	40,516	25,728	121,487	98,386
Depreciation and amortization	7,150	5,665	20,209	15,848
Total administrative expenses	131,584	98,058	380,095	297,383
Total operating expenses	162,496	124,450	470,611	378,332
Operating income	34,036	50,556	149,876	165,930
Interest expense		(260)	(19)	(794)
Other income (expense), net	246	195	(522)	(168)
Income before income taxes	34,282	50,491	149,335	164,968
Provision for income taxes	6,800	11,339	30,249	29,772
Net income	$ 27,482	$ 39,152	$ 119,086	$ 135,196
Earnings per share, basic	$ 0.48	$ 0.68	$ 2.07	$ 2.35
Earnings per share, diluted	$ 0.47	$ 0.67	$ 2.04	$ 2.31
Weighted average shares outstanding:
Basic	57,603	57,654	57,609	57,528
Diluted	58,171	58,383	58,312	58,403
Recurring [Member]
Revenues
Total revenues	$ 192,664	$ 171,405	$ 609,109	$ 534,267
Implementation and Other [Member]
Revenues
Total revenues	$ 3,868	$ 3,601	$ 11,378	$ 9,995