GOODWILL AND INTANGIBLE ASSETS (Details - Balance Sheet)					1 Months Ended	6 Months Ended	12 Months Ended
	Jan. 10, 2019 USD ($)	Oct. 31, 2018 USD ($)	Jul. 23, 2018 USD ($)	Jun. 11, 2018 USD ($)	Nov. 30, 2018 segment	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Goodwill [Line Items]
Impairment losses during period related to goodwill							$ 0
Balance of goodwill and intangible assets, net
Goodwill							903,227,000	$ 903,227,000	$ 903,227,000	$ 831,435,000	$ 596,456,000
Accumulated impairment losses							(483,088,000)	(483,088,000)	(483,088,000)	(483,088,000)	(483,088,000)
Net goodwill							420,139,000	420,139,000	420,139,000	348,347,000	113,368,000
Intangible assets with indefinite lives							10,142,000	10,142,000	10,142,000	10,142,000
Intangible assets with definite lives, net							171,438,000	171,438,000	171,438,000	195,557,000
Total intangible assets, net							181,580,000	$ 181,580,000	$ 181,580,000	205,699,000
Acquisition related costs							600,000			6,900,000	$ 1,000,000.0
Number of reportable segments					1			3	3
Impairment charges related to trade names and trademarks							0
Ovation
Goodwill [Line Items]
Total purchase price				$ 17,900,000			17,871,000
Increase to goodwill due to acquisitions							20,000			11,260,000
Impairment losses during period related to goodwill							0			0
Balance of goodwill and intangible assets, net
Net goodwill				$ 11,300,000			11,280,000	$ 11,280,000	$ 11,280,000
Acquisition related costs							400,000
Student Loan Hero
Goodwill [Line Items]
Total purchase price			$ 60,400,000				60,418,000
Increase to goodwill due to acquisitions										40,856,000
Impairment losses during period related to goodwill										0
Balance of goodwill and intangible assets, net
Net goodwill			$ 40,900,000				40,856,000	40,856,000	40,856,000
Acquisition related costs							500,000
QuoteWizard
Goodwill [Line Items]
Total purchase price		$ 313,400,000					313,355,000
Increase to goodwill due to acquisitions							33,000			182,863,000
Impairment losses during period related to goodwill							0			$ 0
Balance of goodwill and intangible assets, net
Net goodwill		$ 182,900,000					182,896,000	182,896,000	182,896,000
Acquisition related costs							4,800,000
ValuePenguin
Goodwill [Line Items]
Total purchase price	$ 106,200,000						106,232,000
Earnings of acquiree since acquisition date						$ 3,100,000
Increase to goodwill due to acquisitions							71,739,000
Impairment losses during period related to goodwill							0
Balance of goodwill and intangible assets, net
Net goodwill	$ 71,700,000						71,739,000	71,739,000	71,739,000
Revenue of acquirees since acquisition date							19,800,000
Acquisition related costs							100,000
Home
Balance of goodwill and intangible assets, net
Goodwill							59,300,000	59,300,000	59,300,000
Consumer
Balance of goodwill and intangible assets, net
Goodwill							166,100,000	166,100,000	166,100,000
Insurance
Balance of goodwill and intangible assets, net
Goodwill							$ 194,700,000	$ 194,700,000	$ 194,700,000