CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues [Abstract]
Net revenue	$ 653,664	$ 611,870	$ 626,115	$ 540,317	$ 309,879	$ 275,659	$ 261,994	$ 255,658	$ 2,431,966	$ 1,103,190	$ 896,377
Operating expenses (income):
Direct operating expenses, excluding depreciation and amortization									993,405	381,997	302,257
Selling, general, and administrative expenses, excluding depreciation and amortization									591,986	263,606	232,480
Amortization of broadcast rights									105,403	57,145	59,836
Amortization of intangible assets									159,500	46,572	48,475
Depreciation									100,658	51,300	47,222
Goodwill and intangible assets impairment									19,985	15,262
Gain on disposal of stations, net									(57,716)
Total operating expenses									1,913,221	815,882	690,270
Income from operations	140,837	129,072	138,685	110,151	92,475	72,897	64,007	57,929	518,745	287,308	206,107
Interest expense, net									(241,195)	(116,081)	(80,520)
Loss on extinguishment of debt									(34,882)
Other expenses									(1,284)	(555)	(517)
Income before income taxes	87,519	74,085	80,777	(997)	47,101	43,149	43,283	37,139	241,384	170,672	125,070
Income tax benefit (expense)									233,943	(77,572)	(48,687)
Net income (loss)									475,327	93,100	76,383
Net (income) loss attributable to noncontrolling interests									(330)	(1,563)	1,301
Net income attributable to Nexstar Media Group, Inc.	$ 378,481	$ 46,475	$ 43,992	$ 6,049	$ 20,482	$ 24,799	$ 24,529	$ 21,727	$ 474,997	$ 91,537	$ 77,684
Net income per common share attributable to Nexstar Media Group, Inc.:
Basic	$ 8.27	$ 1.01	$ 0.94	$ 0.14	$ 0.67	$ 0.81	$ 0.80	$ 0.71	$ 10.38	$ 2.98	$ 2.50
Diluted	$ 8.03	$ 0.98	$ 0.91	$ 0.13	$ 0.64	$ 0.78	$ 0.78	$ 0.69	$ 10.07	$ 2.89	$ 2.42
Weighted average number of common shares outstanding:
Basic	45,754	46,107	46,931	44,200	30,713	30,695	30,680	30,658	45,754	30,687	31,100
Diluted	47,149	47,452	48,195	45,419	31,798	31,698	31,620	31,538	47,149	31,664	32,091
Dividends declared per common share									$ 1.20	$ 0.96	$ 0.76
Net income									$ 475,327	$ 93,100	$ 76,383
Other comprehensive income:
Change in unrecognized amounts included in pension and postretirement obligations, net of tax of $2,160									6,140
Total comprehensive income									481,467	93,100	76,383
Total comprehensive income attributable to noncontrolling interests									(330)	(1,563)	1,301
Total comprehensive income attributable to Nexstar Media Group, Inc.									$ 481,137	$ 91,537	$ 77,684