Condensed Consolidating Financial Information - Condensed Consolidated Balance Sheets (Details) - USD ($) $ in Thousands		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents		$ 115,652	$ 87,680	$ 43,416	$ 131,912
Accounts receivable, net		562,943	218,058
Spectrum asset		305,764
Other current assets		71,859	57,479
Total current assets		1,056,218	363,217
Property and equipment, net		734,138	276,153
Goodwill		2,142,846	473,304	451,662
FCC licenses		1,767,638	542,524	489,335
Other intangible assets, net		1,581,626	324,737
Restricted cash			901,080
Other noncurrent assets		199,181	85,070
Total assets	[1]	7,481,647	2,966,085
Current liabilities:
Current portion of debt		92,808	28,093
Accounts payable		31,136	19,754
Liability to surrender spectrum asset		314,087
Other current liabilities		232,672	141,731
Total current liabilities		670,703	189,578
Debt		4,269,652	2,314,326
Deferred tax liabilities		619,441	132,008
Other noncurrent liabilities		340,541	45,819
Total liabilities	[1]	5,900,337	2,681,731
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		1,570,614	169,141
Noncontrolling interests in consolidated variable interest entities		10,696	115,213
Total liabilities and stockholders' equity		7,481,647	2,966,085
Eliminations [Member]
Current assets:
Amounts due from consolidated entities		(148,340)	(86,438)
Total current assets		(148,340)	(86,438)
Investments in subsidiaries		(726,651)	(294,650)
Amounts due from consolidated entities		(970,207)	(66,170)
Property and equipment, net		(75)	(75)
Total assets		(1,845,273)	(447,333)
Current liabilities:
Amounts due to consolidated entities		(148,340)	(86,438)
Total current liabilities		(148,340)	(86,438)
Amounts due to consolidated entities		(970,418)	(66,380)
Total liabilities		(1,118,758)	(152,818)
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		(726,515)	(294,515)
Total liabilities and stockholders' equity		(1,845,273)	(447,333)
Nexstar [Member] | Reportable Legal Entities [Member]
Current assets:
Investments in subsidiaries		617,297	256,391
Amounts due from consolidated entities		970,207
Total assets		1,587,504	256,391
Current liabilities:
Amounts due to consolidated entities			66,380
Total liabilities			66,380
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		1,587,504	190,011
Total liabilities and stockholders' equity		1,587,504	256,391
Nexstar Broadcasting [Member] | Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents		90,860	75,830	27,492	130,472
Accounts receivable, net		484,096	184,921
Amounts due from consolidated entities		55,417	5,623
Spectrum asset		279,069
Other current assets		64,256	53,762
Total current assets		973,698	320,136
Investments in subsidiaries		109,354	38,259
Amounts due from consolidated entities			66,170
Property and equipment, net		697,898	244,623
Goodwill		1,959,386	380,164
FCC licenses		1,615,830	468,963
Other intangible assets, net		1,476,297	258,502
Restricted cash			901,080
Other noncurrent assets		189,303	72,070
Total assets		7,021,766	2,749,967
Current liabilities:
Current portion of debt		36,243	19,759
Accounts payable		24,293	16,234
Liability to surrender spectrum asset		286,740
Other current liabilities		192,827	118,049
Total current liabilities		540,103	154,042
Debt		4,024,129	2,045,827
Amounts due to consolidated entities		714,408
Deferred tax liabilities		613,227	118,155
Other noncurrent liabilities		322,572	33,959
Total liabilities		6,214,439	2,351,983
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		807,327	289,290
Noncontrolling interests in consolidated variable interest entities			108,694
Total liabilities and stockholders' equity		7,021,766	2,749,967
Mission [Member] | Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents		9,524	6,478	4,367	889
Accounts receivable, net		14,717	12,332
Amounts due from consolidated entities		92,923	80,815
Other current assets		2,070	1,337
Total current assets		119,234	100,962
Property and equipment, net		18,454	19,564
Goodwill		33,187	33,187
FCC licenses		43,102	43,102
Other intangible assets, net		15,841	17,922
Other noncurrent assets		2,645	11,144
Total assets		232,463	225,881
Current liabilities:
Current portion of debt		2,314	2,334
Accounts payable		1,090	524
Other current liabilities		13,310	9,017
Total current liabilities		16,714	11,875
Debt		223,428	221,431
Other noncurrent liabilities		7,626	9,832
Total liabilities		247,768	243,138
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		(15,305)	(21,257)
Noncontrolling interests in consolidated variable interest entities			4,000
Total liabilities and stockholders' equity		232,463	225,881
Non-Guarantors [Member] | Reportable Legal Entities [Member]
Current assets:
Cash and cash equivalents		15,268	5,372	$ 11,557	$ 551
Accounts receivable, net		64,130	20,805
Spectrum asset		26,695
Other current assets		5,533	2,380
Total current assets		111,626	28,557
Property and equipment, net		17,861	12,041
Goodwill		150,273	59,953
FCC licenses		108,706	30,459
Other intangible assets, net		89,488	48,313
Other noncurrent assets		7,233	1,856
Total assets		485,187	181,179
Current liabilities:
Current portion of debt		54,251	6,000
Accounts payable		5,753	2,996
Liability to surrender spectrum asset		27,347
Amounts due to consolidated entities		148,340	86,438
Other current liabilities		26,535	14,665
Total current liabilities		262,226	110,099
Debt		22,095	47,068
Amounts due to consolidated entities		256,010
Deferred tax liabilities		6,214	13,853
Other noncurrent liabilities		10,343	2,028
Total liabilities		556,888	173,048
Total Nexstar Media Group, Inc. stockholders' equity (deficit)		(82,397)	5,612
Noncontrolling interests in consolidated variable interest entities		10,696	2,519
Total liabilities and stockholders' equity		$ 485,187	$ 181,179

[1] The consolidated total assets as of December 31, 2017 and 2016 include certain assets held by consolidated VIEs of $426.9 million and $226.2 million, respectively, which are not available to be used to settle the obligations of Nexstar. The consolidated total liabilities as of December 31, 2017 and 2016 include certain liabilities of consolidated VIEs of $81.8 million and $39.2 million, respectively, for which the creditors of the VIEs have no recourse to the general credit of Nexstar. See Note 2 for additional information.