SEGMENT INFORMATION (Details) $ in Thousands			12 Months Ended
Sep. 30, 2019 segment	Oct. 31, 2018 segment	Dec. 31, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
SEGMENT INFORMATION
Number of operating segments \| segment			3
Number of reportable segments \| segment	1	1	3
Revenue			$ 909,990	$ 1,106,603	$ 764,865
Segment cost of revenue and marketing expense			540,517	674,285	459,728
Segment profit (loss)			369,473	432,318	305,137
Cost of revenue (exclusive of cost of advertising re-sold to third parties included above)			53,408	45,624	27,587
Brand and other marketing expense			77,973	83,650	49,375
General and administrative expense			129,101	116,847	101,219
Product development			43,636	39,953	26,958
Depreciation			14,201	10,998	7,385
Amortization of intangibles			53,078	55,241	23,468
Change in fair value of contingent consideration			5,327	28,402	10,788
Severance			295	1,026	2,352
Litigation settlements and contingencies			(943)	(151)	(186)
Operating (loss) income			(6,603)	50,728	56,191
Interest expense, net			(36,300)	(20,271)	(12,437)
Other income (expense)			376	524	(10)
(Loss) income before income taxes			(42,527)	30,981	43,744
Home
SEGMENT INFORMATION
Revenue			320,992	277,935	319,176
Segment cost of revenue and marketing expense			188,869	174,814	214,475
Segment profit (loss)			132,123	103,121	104,701
Consumer
SEGMENT INFORMATION
Revenue			253,198	515,037	395,615
Segment cost of revenue and marketing expense			146,308	301,852	207,891
Segment profit (loss)			106,890	213,185	187,724
Insurance
SEGMENT INFORMATION
Revenue			333,765	284,792	31,369
Segment cost of revenue and marketing expense			202,623	170,153	20,011
Segment profit (loss)			131,142	114,639	11,358
Other
SEGMENT INFORMATION
Revenue			2,035	28,839	18,705
Segment cost of revenue and marketing expense			2,717	27,466	17,351
Segment profit (loss)			$ (682)	$ 1,373	$ 1,354

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