Consolidated Statements of Income - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Revenues
Total revenues	$ 1,055,524	$ 841,434	$ 737,671
Cost of revenues
Operating expenses	130,475	97,778	89,336
Depreciation and amortization	31,411	25,768	20,411
Total cost of revenues	161,886	123,546	109,747
Administrative expenses
Sales and marketing	275,994	235,716	179,286
Research and development	118,426	90,244	73,080
General and administrative	209,840	178,200	127,534
Depreciation and amortization	35,811	27,605	21,800
Total administrative expenses	640,071	531,765	401,700
Total operating expenses	801,957	655,311	511,447
Operating income	253,567	186,123	226,224
Interest expense		(19)	(940)
Other income (expense), net	2,395	(168)	803
Income before income taxes	255,962	185,936	226,087
Provision for income taxes	60,002	42,483	45,511
Net income	$ 195,960	$ 143,453	$ 180,576
Earnings per share, basic	$ 3.39	$ 2.49	$ 3.14
Earnings per share, diluted	$ 3.37	$ 2.46	$ 3.09
Weighted average shares outstanding:
Basic	57,885	57,620	57,561
Diluted	58,191	58,285	58,395
Recurring [Member]
Revenues
Total revenues	$ 1,036,691	$ 825,856	$ 724,428
Implementation and Other [Member]
Revenues
Total revenues	$ 18,833	$ 15,578	$ 13,243