GOODWILL, INDEFINITE-LIVED INTANGIBLE ASSETS AND OTHER INTANGIBLE ASSETS - Change in Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	$ 2,124,033	$ 1,990,746
Acquisitions		133,392
Measurement period adjustments related to prior year acquisitions	(131)	307
Disposition of assets		(412)
Goodwill, net	2,123,902	2,124,033
VIEs which are not primary beneficiary
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	800
Goodwill, net	800	800
Broadcast
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	2,053,410	1,933,831
Acquisitions		119,426
Measurement period adjustments related to prior year acquisitions	1,369	153
Disposition of assets		0
Goodwill, net	2,054,779	2,053,410
Other
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	70,623	56,915
Acquisitions		13,966
Measurement period adjustments related to prior year acquisitions	(1,500)	154
Disposition of assets		(412)
Goodwill, net	$ 69,123	$ 70,623

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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