ACQUISITIONS (Details) (USD $)	3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended		0 Months Ended	3 Months Ended		9 Months Ended			0 Months Ended				3 Months Ended	9 Months Ended	0 Months Ended				3 Months Ended	9 Months Ended		0 Months Ended		0 Months Ended				12 Months Ended	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014 Measurement period adjustments	Sep. 30, 2014 Measurement period adjustments	Sep. 30, 2014 5.625% Senior Unsecured Notes, due 2024	Aug. 08, 2013 Fisher station market	Sep. 30, 2014 Fisher	Sep. 30, 2013 Fisher	Sep. 30, 2014 Fisher	Sep. 30, 2013 Fisher	Sep. 30, 2014 Fisher KIDK and KXPI station	Aug. 08, 2013 Fisher Network affiliations	Aug. 08, 2013 Fisher Decaying advertiser base	Aug. 08, 2013 Fisher Other intangible assets	Nov. 22, 2013 Barrington Broadcasting Company, LLC market station	Sep. 30, 2014 Barrington Broadcasting Company, LLC	Sep. 30, 2014 Barrington Broadcasting Company, LLC	Nov. 22, 2013 Barrington Broadcasting Company, LLC Network affiliations	Nov. 22, 2013 Barrington Broadcasting Company, LLC Decaying advertiser base	Nov. 22, 2013 Barrington Broadcasting Company, LLC Other intangible assets	Aug. 01, 2014 Allbritton	Sep. 30, 2014 Allbritton	Sep. 30, 2014 Allbritton	Jul. 31, 2014 Allbritton station	Sep. 03, 2014 Allbritton WHTM	Aug. 01, 2014 Allbritton 5.625% Senior Unsecured Notes, due 2024	Aug. 01, 2014 Allbritton Network affiliations	Aug. 01, 2014 Allbritton Decaying advertiser base	Aug. 01, 2014 Allbritton Other intangible assets	May 31, 2013 CMG market station	Dec. 31, 2013 TTBG LLC market station	Sep. 30, 2014 Other acquisitions	Sep. 30, 2014 Other acquisitions	Sep. 30, 2013 Other acquisitions	Sep. 30, 2014 Other acquisitions	Sep. 30, 2013 Other acquisitions	Dec. 31, 2013 Other acquisitions market station	Dec. 31, 2013 Other acquisitions Network affiliations	Dec. 31, 2013 Other acquisitions Decaying advertiser base	Dec. 31, 2013 Other acquisitions Other intangible assets
Acquisitions
Cash paid								$ 373,200,000									$ 370,000,000						$ 985,000,000											$ 33,000,000					$ 272,700,000
Cash paid for acquisition (in dollars per share)								$ 41.0
Number of television stations								22					2				24									9						5	10						19
Number of markets								8									15															4	4						10
Number of stations to which sales services were provided																	5
Number of radio stations in Seattle market								4
Working capital adjustment																	(2,400,000)						52,100,000																9,500,000
Proceeds from the sale of broadcast assets																											83,400,000
Working capital adjustment in disposition																											200,000
Noncontrolling interests related to the license assets																	7,500,000																						700,000
Price of assets acquired/sold													6,300,000
Allocated fair value of acquired assets and assumed liabilities
Cash								13,531,000
Accounts receivable								29,485,000															38,542,000																8,226,000
Prepaid expenses and other current assets								19,133,000									681,000						21,482,000											6,000	6,000		6,000		5,217,000
Program contract costs								11,427,000									3,960,000						1,204,000											100,000	100,000		100,000		6,050,000
Property and equipment					45,000,000	45,000,000		73,968,000									73,621,000						46,600,000											10,070,000	10,070,000		10,070,000		67,429,000
Broadcast licenses					22,000,000	22,000,000		29,771,000									2,948,000						5,000,000											25,000	25,000		25,000		4,395,000
Interest rate (as a percent)							5.625%																					5.625%
Definite-lived intangible assets								166,378,000						117,500,000	18,100,000	30,800,000	217,818,000			101,000,000	42,000,000	74,800,000	589,100,000						391,100,000	35,600,000	162,400,000			20,384,000	20,384,000		20,384,000		157,820,000
Other assets								7,683,000															20,352,000																1,394,000
Assets held for sale								6,339,000															83,200,000
Accrued liabilities																																							(3,926,000)
Accounts payable and accrued liabilities								(20,127,000)									(2,725,000)						(7,901,000)
Program contracts payable								(10,977,000)									(3,813,000)						(1,140,000)											(100,000)	(100,000)		(100,000)		(6,331,000)
Deferred tax liabilities					(29,000,000)	(29,000,000)		(74,177,000)															(266,313,000)																(1,882,000)
Other long-term liabilities								(22,127,000)									(65,000)						(17,025,000)																(10,550,000)
Fair value of identifiable net assets acquired								230,307,000									292,425,000						513,101,000											30,485,000	30,485,000		30,485,000		227,842,000
Goodwill						(56,000,000)		143,942,000									75,261,000						523,953,000														2,521,000		55,036,000
Depreciation expense	25,342,000	17,408,000	74,972,000	47,108,000	1,200,000	2,500,000
Amortization expense					1,200,000	2,500,000
Less: fair value of non-controlling interests								(1,053,000)
Total								373,196,000									367,686,000						1,037,054,000											33,006,000	33,006,000		33,006,000		282,878,000
Goodwill deductible for tax purposes								11,100,000
Amortization period														15 years	10 years					15 years	10 years								15 years	10 years										15 years	10 years
Weighted average life																14 years						15 years									15 years											14 years
Net broadcast revenues	448,056,000	303,028,000	1,226,088,000	835,223,000					45,300,000	25,900,000	129,600,000	25,900,000						42,800,000	123,200,000					41,200,000	41,200,000										35,200,000	5,000,000	98,700,000	14,800,000
Operating income									6,100,000	8,200,000	12,600,000	8,200,000						6,500,000	22,200,000					9,000,000	9,000,000										14,200,000	3,400,000	22,700,000	5,800,000
Pro Forma Information
Total revenues	500,133,000	440,104,000	1,469,241,000	1,286,344,000
Net Income from continuing operations	45,028,000	17,945,000	107,949,000	31,947,000
Net Income attributable to Sinclair Broadcast Group from continuing operations	$ 44,601,000	$ 17,636,000	$ 106,757,000	$ 31,532,000
Basic earnings per share attributable to Sinclair Broadcast Group from continuing operations (in dollars per share)	$ 0.46	$ 0.18	$ 1.09	$ 0.35
Diluted earnings per share attributable to Sinclair Broadcast Group from continuing operations (in dollars per share)	$ 0.45	$ 0.18	$ 1.08	$ 0.34