Segment Data - Summary of Segment Financial Information (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Segment Reporting Information [Line Items]
Net revenue		$ 1,118,203	$ 663,575	$ 3,124,658	$ 1,939,234
Depreciation		36,611	29,363	107,787	84,890
Amortization of intangible assets		69,265	42,443	209,360	115,538
Income (loss) from operations		343,597	121,615	844,865	398,633
Goodwill		2,861,314		2,861,314		$ 2,996,875
Total assets	[1]	13,290,502		13,290,502		13,989,737
Broadcast [Member]
Segment Reporting Information [Line Items]
Net revenue		1,094,804	637,148	3,060,279	1,858,226
Depreciation		31,096	26,538	91,187	75,587
Amortization of intangible assets		68,591	37,215	206,617	98,830
Income (loss) from operations		377,172	189,408	958,592	550,001
Goodwill		2,861,314		2,861,314		2,996,875
Total assets		12,169,206		12,169,206		12,918,966
Other [Member]
Segment Reporting Information [Line Items]
Net revenue		23,399	26,427	64,379	81,008
Depreciation		5,515	2,825	16,600	9,303
Amortization of intangible assets		674	5,228	2,743	16,708
Income (loss) from operations		(33,575)	$ (67,793)	(113,727)	$ (151,368)
Total assets		$ 1,121,296		$ 1,121,296		$ 1,070,771

[1] The consolidated total assets as of September 30, 2020 and December 31, 2019 include certain assets held by consolidated VIEs of $339.6 million and $332.6 million, respectively, which are not available to be used to settle the obligations of Nexstar. The consolidated total liabilities as of September 30, 2020 and December 31, 2019 include certain liabilities of consolidated VIEs of $59.8 million and $61.7 million, respectively, for which the creditors of the VIEs have no recourse to the general credit of Nexstar. See Note 2 for additional information.