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Represents the amount used to determine annual LMA fees required to be paid to related party.

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Represents the percentage of each station's net broadcast revenue due to the related party used to determine amount of annual LMA fees required to be paid.

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Percentage of capital stock or assets to be acquired in business combination.

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RELATED PERSON TRANSACTIONS - Cunningham Broadcasting Corporation (Details) $ in Millions	1 Months Ended		3 Months Ended								12 Months Ended
	Aug. 31, 2016 USD ($)	Apr. 30, 2016 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) renewal	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Related person transactions
Debt and lease obligations			$ 12,551.0								$ 12,551.0
Deferred financing costs			19.0				$ 222.0				19.0	$ 222.0
Revenue			1,512.0	$ 1,539.0	$ 1,283.0	$ 1,609.0	1,622.0	$ 1,125.0	$ 771.0	$ 722.0	5,943.0	4,240.0	$ 3,055.0
Consolidated VIEs
Related person transactions
Debt and lease obligations			$ 16.0				20.0				16.0	20.0
LMA \| Cunningham
Related person transactions
Payments to related party											$ 8.0	8.0	10.0
Cunningham \| Cunningham License Related Assets
Related person transactions
Agreement renewal period											8 years
Revenue											$ 157.0	155.0	171.0
Cunningham \| Affiliated Entity
Related person transactions
Percentage of the total capital stock held in the related party, none of which have voting rights			100.00%								100.00%
Liabilities treated as prepayment of purchase price			$ 54.0				51.0				$ 54.0	51.0
Remaining purchase price			54.0				54.0				54.0	54.0
Purchase options broadcast stations			0.2								0.2
Equipment purchase agreement, consideration amount		$ 1.0
Equipment purchase agreement, annual service consideration		$ 0.2
Share service agreement, annual service consideration	$ 1.0
Cunningham \| Affiliated Entity \| Consolidated VIEs
Related person transactions
Debt and lease obligations			8.0								8.0
Deferred financing costs			$ 0.4								$ 0.4
Cunningham \| LMA \| Affiliated Entity
Related person transactions
Number of additional renewal terms \| renewal											2
Agreement renewal period											5 years
Cunningham \| Minimum \| LMA \| Affiliated Entity
Related person transactions
Percentage of net broadcast revenue used to determine annual LMA fees required to be paid			3.00%								3.00%
Amount used to determine annual LMA fees required to be paid			$ 5.0								$ 5.0
Annual increase in aggregate purchase price (as a percent)			6.00%								6.00%
Guarantee Obligations
Related person transactions
Unconditional and irrevocably guaranteed debt			$ 49.0				$ 57.0				$ 49.0	57.0
Guarantee Obligations \| Cunningham \| Affiliated Entity
Related person transactions
Unconditional and irrevocably guaranteed debt			$ 41.0								41.0
Eliminations
Related person transactions
Revenue											$ (184.0)	$ (123.0)	$ (94.0)