CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Revenues		$ 1,390,997	$ 1,416,722	$ 1,158,829
Operating costs and expenses:
Cost of revenues	[1]	195,554	188,053	178,403
Sales and marketing	[1]	490,777	493,049	366,359
Research, development and engineering	[1]	74,093	78,874	57,148
General and administrative	[1]	404,263	456,777	418,579
Goodwill impairment on business		27,369	32,629	0
Total operating costs and expenses		1,192,056	1,249,382	1,020,489
Income from operations		198,941	167,340	138,340
Interest expense, net		(33,842)	(72,023)	(56,188)
Gain (loss) on debt extinguishment, net		11,505	(5,274)	0
(Loss) gain on sale of businesses		0	(21,798)	17,122
Unrealized (loss) gain on short-term investments held at the reporting date, net		(7,145)	298,490	0
Loss on investments, net		(46,743)	(16,677)	(20,991)
Other income, net		8,437	1,293	65
Income from continuing operations before income tax (expense) benefit and changes from equity method investment		131,153	351,351	78,348
Income tax (expense) benefit		(57,957)	14,199	(38,350)
(Loss) income from equity method investment, net of income taxes		(7,730)	35,845	(11,338)
Net income from continuing operations		65,466	401,395	28,660
(Loss) income from discontinued operations, net of income taxes		(1,709)	95,319	122,008
Net income		$ 63,757	$ 496,714	$ 150,668
Net income per common share from continuing operations:
Basic (in dollars per share)		$ 1.39	$ 8.74	$ 0.62
Diluted (in dollars per share)		1.39	8.38	0.61
Net (loss) income per common share from discontinued operations:
Basic (in dollars per share)		(0.04)	2.08	2.62
Diluted (in dollars per share)		(0.04)	1.99	2.58
Net income per common share:
Basic (in dollars per share)		1.36	10.81	3.24
Diluted (in dollars per share)		$ 1.36	$ 10.37	$ 3.18
Weighted average shares outstanding:
Basic (in shares)		46,954,558	45,893,928	46,308,825
Diluted (in shares)		47,025,849	47,862,745	47,115,609
Share-based compensation expense		$ 26,601	$ 24,129	$ 22,520
Cost of revenues
Weighted average shares outstanding:
Share-based compensation expense		341	306	332
Sales and marketing
Weighted average shares outstanding:
Share-based compensation expense		3,083	1,288	1,011
Research, development and engineering
Weighted average shares outstanding:
Share-based compensation expense		2,503	1,984	1,396
General and administrative
Weighted average shares outstanding:
Share-based compensation expense		$ 20,674	$ 20,551	$ 19,781

[1] (1) Includes share-based compensation expense as follows: Cost of revenues$341 $306 $332 Sales and marketing3,083 1,288 1,011 Research, development and engineering2,503 1,984 1,396 General and administrative20,674 20,551 19,781 Total$26,601 $24,129 $22,520