CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 1,106,603	$ 764,865	$ 617,736
Costs and expenses:
Cost of revenue (exclusive of depreciation and amortization shown separately below)	68,379	36,399	17,223
Selling and marketing expense	735,180	500,291	432,784
General and administrative expense	116,847	101,219	71,541
Product development	39,953	26,958	17,925
Depreciation	10,998	7,385	7,085
Amortization of intangibles	55,241	23,468	12,992
Change in fair value of contingent consideration	28,402	10,788	23,931
Severance	1,026	2,352	404
Litigation settlements and contingencies	(151)	(186)	718
Total costs and expenses	1,055,875	708,674	584,603
Operating income	50,728	56,191	33,133
Other (expense) income, net:
Interest expense, net	(20,271)	(12,437)	(7,028)
Other income (expense)	524	(10)	(396)
Income before income taxes	30,981	43,744	25,709
Income tax benefit (expense)	8,479	65,575	(6,291)
Net income from continuing operations	39,460	109,319	19,418
Loss from discontinued operations, net of tax	(21,632)	(12,820)	(3,840)
Net income	$ 17,828	$ 96,499	$ 15,578
Weighted average shares outstanding:
Weighted average basic common shares (in shares)	12,834	12,504	11,945
Weighted average diluted common shares (in shares)	14,619	14,097	13,682
Income per share from continuing operations:
Basic (in dollars per share)	$ 3.07	$ 8.74	$ 1.63
Diluted (in dollars per share)	2.70	7.75	1.42
Loss per share from discontinued operations:
Basic (in dollars per share)	(1.69)	(1.03)	(0.32)
Diluted (in dollars per share)	(1.48)	(0.91)	(0.28)
Net income per share:
Basic (in dollars per share)	1.39	7.72	1.30
Diluted (in dollars per share)	$ 1.22	$ 6.85	$ 1.14