CONDENSED CONSOLIDATING FINANCIAL STATEMENTS - Statement of Operations and Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	$ 730,143	$ 652,234	$ 1,395,496	$ 1,279,170
Media program and production expenses	300,858	269,486	589,407	527,887
Selling, general and administrative	180,479	152,097	351,974	297,394
Depreciation, amortization and other operating expenses	117,224	111,802	215,218	177,411
Total operating expenses	598,561	533,385	1,156,599	1,002,692
Operating income	131,582	118,849	238,897	276,478
Equity in earnings of consolidated subsidiaries	0	0	0	0
Interest expense	(92,271)	(50,959)	(162,013)	(108,277)
Loss from extinguishment of debt	0	0	0	(1,404)
Other income (expense)	(13,299)	3,025	(22,505)	3,400
Total other expense, net	(105,570)	(47,934)	(184,518)	(106,281)
Income tax benefit (provision)	3,297	(24,880)	18,925	(53,459)
NET INCOME	29,309	46,035	73,304	116,738
Net income attributable to the noncontrolling interests	(1,268)	(1,390)	(2,139)	(14,891)
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	28,041	44,645	71,165	101,847
Comprehensive income	29,309	46,035	73,304	116,738
Reportable legal entities | Sinclair Broadcast Group, Inc.
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	0	0	0	0
Media program and production expenses	0	0	0	0
Selling, general and administrative	2,874	2,292	5,471	3,588
Depreciation, amortization and other operating expenses	19	225	38	491
Total operating expenses	2,893	2,517	5,509	4,079
Operating income	(2,893)	(2,517)	(5,509)	(4,079)
Equity in earnings of consolidated subsidiaries	29,345	45,927	74,383	104,116
Interest expense	(1)	(34)	(1)	(71)
Loss from extinguishment of debt	0		0	0
Other income (expense)	642	723	1,323	824
Total other expense, net	29,986	46,616	75,705	104,869
Income tax benefit (provision)	948	546	969	1,057
NET INCOME	28,041	44,645	71,165	101,847
Net income attributable to the noncontrolling interests	0	0	0	0
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	28,041	44,645	71,165	101,847
Comprehensive income	28,041	44,645	71,165	101,847
Reportable legal entities | Sinclair Television Group, Inc.
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	0	0	0	0
Media program and production expenses	0	0	0	0
Selling, general and administrative	26,585	22,412	48,339	41,370
Depreciation, amortization and other operating expenses	1,134	1,651	2,384	3,376
Total operating expenses	27,719	24,063	50,723	44,746
Operating income	(27,719)	(24,063)	(50,723)	(44,746)
Equity in earnings of consolidated subsidiaries	128,164	96,600	299,934	184,405
Interest expense	(90,635)	(49,379)	(158,803)	(104,083)
Loss from extinguishment of debt	0		0	(1,404)
Other income (expense)	3,256	1,128	5,551	1,928
Total other expense, net	40,785	48,349	146,682	80,846
Income tax benefit (provision)	22,056	24,636	37,454	49,741
NET INCOME	35,122	48,922	133,413	85,841
Net income attributable to the noncontrolling interests	0	0	0	0
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	35,122	48,922	133,413	85,841
Comprehensive income	35,122	48,922	133,413	85,841
Reportable legal entities | Guarantor Subsidiaries and KDSM, LLC
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	680,130	623,087	1,305,814	1,218,326
Media program and production expenses	285,940	257,977	559,355	506,426
Selling, general and administrative	147,180	124,450	290,481	246,884
Depreciation, amortization and other operating expenses	84,573	87,564	90,989	178,078
Total operating expenses	517,693	469,991	940,825	931,388
Operating income	162,437	153,096	364,989	286,938
Equity in earnings of consolidated subsidiaries	(185)	93	245	143
Interest expense	(989)	(1,425)	(1,961)	(2,545)
Loss from extinguishment of debt	0		0	0
Other income (expense)	(14,345)	(1,895)	(27,706)	(1,399)
Total other expense, net	(15,519)	(3,227)	(29,422)	(3,801)
Income tax benefit (provision)	(17,607)	(51,842)	(33,283)	(96,071)
NET INCOME	129,311	98,027	302,284	187,066
Net income attributable to the noncontrolling interests	0	0	0	0
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	129,311	98,027	302,284	187,066
Comprehensive income	129,311	98,027	302,284	187,066
Reportable legal entities | Non- Guarantor Subsidiaries
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	71,730	50,158	129,741	101,014
Media program and production expenses	33,175	30,476	65,195	58,920
Selling, general and administrative	4,352	2,919	8,636	5,552
Depreciation, amortization and other operating expenses	33,223	23,136	124,231	(3,315)
Total operating expenses	70,750	56,531	198,062	61,157
Operating income	980	(6,373)	(68,321)	39,857
Equity in earnings of consolidated subsidiaries	0	0	0	0
Interest expense	(4,643)	(4,149)	(9,193)	(11,772)
Loss from extinguishment of debt	0		0	0
Other income (expense)	(2,852)	3,069	(1,673)	2,047
Total other expense, net	(7,495)	(1,080)	(10,866)	(9,725)
Income tax benefit (provision)	(2,100)	1,780	13,785	(8,186)
NET INCOME	(8,615)	(5,673)	(65,402)	21,946
Net income attributable to the noncontrolling interests	(1,268)	(1,386)	(2,324)	(14,879)
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	(9,883)	(7,059)	(67,726)	7,067
Comprehensive income	(8,615)	(5,673)	(65,402)	21,946
Eliminations
CONDENSED CONSOLIDATING STATEMENT OF OPERATIONS AND COMPREHENSIVE INCOME
Total revenues	(21,717)	(21,011)	(40,059)	(40,170)
Media program and production expenses	(18,257)	(18,967)	(35,143)	(37,459)
Selling, general and administrative	(512)	24	(953)	0
Depreciation, amortization and other operating expenses	(1,725)	(774)	(2,424)	(1,219)
Total operating expenses	(20,494)	(19,717)	(38,520)	(38,678)
Operating income	(1,223)	(1,294)	(1,539)	(1,492)
Equity in earnings of consolidated subsidiaries	(157,324)	(142,620)	(374,562)	(288,664)
Interest expense	3,997	4,028	7,945	10,194
Loss from extinguishment of debt	0		0	0
Other income (expense)	0	0	0	0
Total other expense, net	(153,327)	(138,592)	(366,617)	(278,470)
Income tax benefit (provision)	0	0	0	0
NET INCOME	(154,550)	(139,886)	(368,156)	(279,962)
Net income attributable to the noncontrolling interests	0	(4)	185	(12)
NET INCOME ATTRIBUTABLE TO SINCLAIR BROADCAST GROUP	(154,550)	(139,890)	(367,971)	(279,974)
Comprehensive income	$ (154,550)	$ (139,886)	$ (368,156)	$ (279,962)