Acquisitions - Narrative (Details) $ in Millions					1 Months Ended	6 Months Ended
	Sep. 19, 2019 USD ($) market affiliate station	Aug. 08, 2019 USD ($) radio_station	Jun. 18, 2019 USD ($)	Jan. 02, 2019 USD ($)	Apr. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2019 station
Business Acquisition [Line Items]
Number of stations acquired | station							15
Increase in goodwill						$ 18.1
Amortization expense related to intangibles						68.0
Retransmission agreements
Business Acquisition [Line Items]
Reduction in intangible assets						$ 21.3
Nexstar Media Group
Business Acquisition [Line Items]
Number of stations acquired | station	11
Number of markets | market	8
Number of affiliates acquired | affiliate	8
Initial purchase price	$ 769.9
Base purchase price	740.0
Working capital adjustment	$ 29.9
Payment of working capital adjustment					$ 0.8
Dispatch Stations
Business Acquisition [Line Items]
Initial purchase price		$ 560.5
Base purchase price		535.0
Working capital adjustment		$ 25.5
Number of ratio stations acquired | radio_station		2
Justice & Quest
Business Acquisition [Line Items]
Initial purchase price			$ 77.1
Working capital adjustment			$ 4.6
Ownership interest (as a percent)			85.00%
Gray Stations
Business Acquisition [Line Items]
Initial purchase price				$ 109.9
Working capital adjustment				$ 4.9