GOODWILL, INDEFINITE-LIVED INTANGIBLE ASSETS AND OTHER INTANGIBLE ASSETS - Change in Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	$ 2,124.0	$ 2,124.0
Measurement period adjustments related to prior year acquisitions		0.0
Acquisitions	2,621.0
Assets held for sale	(29.0)
Goodwill, net	4,716.0	2,124.0
VIEs which are not primary beneficiary
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	1.0
Goodwill, net	1.0	1.0
Local News and Marketing Services
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	2,055.0	2,053.0
Measurement period adjustments related to prior year acquisitions		2.0
Acquisitions	0.0
Assets held for sale	(29.0)
Goodwill, net	2,026.0	2,055.0
Sports
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	0.0	0.0
Measurement period adjustments related to prior year acquisitions		0.0
Acquisitions	2,615.0
Assets held for sale	0.0
Goodwill, net	2,615.0	0.0
Other
Change in the carrying amount of goodwill related to continuing operations
Goodwill, net	69.0	71.0
Measurement period adjustments related to prior year acquisitions		(2.0)
Acquisitions	6.0
Assets held for sale	0.0
Goodwill, net	$ 75.0	$ 69.0

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.

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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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